Rename master to main

.github/workflows/codeql-analysis.yml

@@ -7,10 +7,10 @@ name: "CodeQL"
 
 on:
   push:
-    branches: [master]
+    branches: [main]
   pull_request:
     # The branches below must be a subset of the branches above
-    branches: [master]
+    branches: [main]
   schedule:
     - cron: '0 13 * * 3'
 

.github/workflows/integration.yml

@@ -3,7 +3,7 @@ name: Integration
 on:
   push:
     branches:
-      - master
+      - main
   schedule:
     - cron: '0 0 * * *'  # daily
 

docs/contributing.rst

@@ -134,12 +134,12 @@ Submitting changes
 ------------------
 
 1. Fork `the GitHub repository`_.
-2. Make a branch off of ``master`` and commit your changes to it.
+2. Make a branch off of ``main`` and commit your changes to it.
 3. Run the tests, check code style, and build the docs as described above.
 4. Optionally, add your name to the end of the :file:`AUTHORS`
    file using the format ``Name <email@domain.com> (url)``, where the
    ``(url)`` portion is optional.
-5. Submit a pull request to the ``master`` branch on GitHub, referencing an
+5. Submit a pull request to the ``main`` branch on GitHub, referencing an
    open issue.
 6. Add a changelog entry.