[readme] Use one badge for minimal checks.

README.md

@@ -15,8 +15,8 @@ Boost.Geometry, part of collection of the [Boost C++ Libraries](http://github.co
 
  Branch     | Build         | Coverage       | Regression | Documentation
 ------------|---------------|----------------|------------|--------------
-**develop** | [![circleci](https://circleci.com/gh/boostorg/geometry/tree/develop.svg?style=shield)](https://circleci.com/gh/boostorg/geometry/tree/develop) <br> [![status](https://github.com/boostorg/geometry/workflows/clang-test-minimal/badge.svg?branch=develop)](https://github.com/boostorg/geometry/actions?query=branch:develop+workflow:clang-test-minimal) <br> [![status](https://github.com/boostorg/geometry/workflows/gcc-test-minimal/badge.svg?branch=develop)](https://github.com/boostorg/geometry/actions?query=branch:develop+workflow:gcc-test-minimal) <br> [![status](https://github.com/boostorg/geometry/workflows/msvc-test-minimal/badge.svg?branch=develop)](https://github.com/boostorg/geometry/actions?query=branch:develop+workflow:msvc-test-minimal) | [![coveralls](https://coveralls.io/repos/github/boostorg/geometry/badge.svg?branch=develop)](https://coveralls.io/github/boostorg/geometry?branch=develop) <br> [![codecov](https://codecov.io/gh/boostorg/geometry/branch/develop/graph/badge.svg)](https://codecov.io/gh/boostorg/geometry/branch/develop) | [![geometry](https://img.shields.io/badge/-geometry-4480cc.png)](http://www.boost.org/development/tests/develop/developer/geometry.html) [![index](https://img.shields.io/badge/-index-4480cc.png)](http://www.boost.org/development/tests/develop/developer/geometry-index.html) [![extensions](https://img.shields.io/badge/-extensions-4480cc.png)](http://www.boost.org/development/tests/develop/developer/geometry-extensions.html) | [![](https://github.com/boostorg/geometry/workflows/documentation/badge.svg?branch=develop)](https://github.com/boostorg/geometry/actions?query=branch:develop+workflow:documentation)
-**master**  | [![circleci](https://circleci.com/gh/boostorg/geometry/tree/master.svg?style=shield)](https://circleci.com/gh/boostorg/geometry/tree/master)   <br> [![status](https://github.com/boostorg/geometry/workflows/clang-test-minimal/badge.svg?branch=master)](https://github.com/boostorg/geometry/actions?query=branch:master+workflow:clang-test-minimal)   <br> [![status](https://github.com/boostorg/geometry/workflows/gcc-test-minimal/badge.svg?branch=master)](https://github.com/boostorg/geometry/actions?query=branch:master+workflow:gcc-test-minimal)   <br> [![status](https://github.com/boostorg/geometry/workflows/msvc-test-minimal/badge.svg?branch=master)](https://github.com/boostorg/geometry/actions?query=branch:master+workflow:msvc-test-minimal)   | [![coveralls](https://coveralls.io/repos/github/boostorg/geometry/badge.svg?branch=master)](https://coveralls.io/github/boostorg/geometry?branch=master)   <br> [![codecov](https://codecov.io/gh/boostorg/geometry/branch/master/graph/badge.svg)](https://codecov.io/gh/boostorg/geometry/branch/master)   | [![geometry](https://img.shields.io/badge/-geometry-4480cc.png)](http://www.boost.org/development/tests/master/developer/geometry.html)  [![index](https://img.shields.io/badge/-index-4480cc.png)](http://www.boost.org/development/tests/master/developer/geometry-index.html) | [![](https://github.com/boostorg/geometry/workflows/documentation/badge.svg?branch=master)](https://github.com/boostorg/geometry/actions?query=branch:master+workflow:documentation)
+**develop** | [![circleci](https://circleci.com/gh/boostorg/geometry/tree/develop.svg?style=shield)](https://circleci.com/gh/boostorg/geometry/tree/develop) <br> [![minimal](https://github.com/boostorg/geometry/workflows/minimal/badge.svg?branch=develop)](https://github.com/boostorg/geometry/actions?query=branch:develop+workflow:minimal) | [![coveralls](https://coveralls.io/repos/github/boostorg/geometry/badge.svg?branch=develop)](https://coveralls.io/github/boostorg/geometry?branch=develop) <br> [![codecov](https://codecov.io/gh/boostorg/geometry/branch/develop/graph/badge.svg)](https://codecov.io/gh/boostorg/geometry/branch/develop) | [![geometry](https://img.shields.io/badge/-geometry-4480cc.png)](http://www.boost.org/development/tests/develop/developer/geometry.html) [![index](https://img.shields.io/badge/-index-4480cc.png)](http://www.boost.org/development/tests/develop/developer/geometry-index.html) [![extensions](https://img.shields.io/badge/-extensions-4480cc.png)](http://www.boost.org/development/tests/develop/developer/geometry-extensions.html) | [![documentation](https://github.com/boostorg/geometry/workflows/documentation/badge.svg?branch=develop)](https://github.com/boostorg/geometry/actions?query=branch:develop+workflow:documentation)
+**master**  | [![circleci](https://circleci.com/gh/boostorg/geometry/tree/master.svg?style=shield)](https://circleci.com/gh/boostorg/geometry/tree/master)   <br> [![minimal](https://github.com/boostorg/geometry/workflows/minimal/badge.svg?branch=master)](https://github.com/boostorg/geometry/actions?query=branch:master+workflow:minimal)   | [![coveralls](https://coveralls.io/repos/github/boostorg/geometry/badge.svg?branch=master)](https://coveralls.io/github/boostorg/geometry?branch=master)   <br> [![codecov](https://codecov.io/gh/boostorg/geometry/branch/master/graph/badge.svg)](https://codecov.io/gh/boostorg/geometry/branch/master)   | [![geometry](https://img.shields.io/badge/-geometry-4480cc.png)](http://www.boost.org/development/tests/master/developer/geometry.html)  [![index](https://img.shields.io/badge/-index-4480cc.png)](http://www.boost.org/development/tests/master/developer/geometry-index.html)                                                                                                                                                          | [![documentation](https://github.com/boostorg/geometry/workflows/documentation/badge.svg?branch=master)](https://github.com/boostorg/geometry/actions?query=branch:master+workflow:documentation)
 
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