remove travis badge

Signed-off-by: Nikolaj Bjorner <nbjorner@microsoft.com>

README.md

@@ -14,9 +14,9 @@ See the [release notes](RELEASE_NOTES) for notes on various stable releases of Z
 
 ## Build status
 
-| Azure Pipelines | TravisCI |
-| --------------- | -------- |
-[![Build Status](https://dev.azure.com/Z3Public/Z3/_apis/build/status/Z3Prover.z3?branchName=master)](https://dev.azure.com/Z3Public/Z3/_build/latest?definitionId=1&branchName=master) | [![Build Status](https://travis-ci.org/Z3Prover/z3.svg?branch=master)](https://travis-ci.org/Z3Prover/z3)
+| Azure Pipelines | 
+| --------------- | 
+[![Build Status](https://dev.azure.com/Z3Public/Z3/_apis/build/status/Z3Prover.z3?branchName=master)](https://dev.azure.com/Z3Public/Z3/_build/latest?definitionId=1&branchName=master) 
 
 [1]: #building-z3-on-windows-using-visual-studio-command-prompt
 [2]: #building-z3-using-make-and-gccclang