[ci skip] [github actions] Rename master to main

.github/workflows/docfx.yml

@@ -2,9 +2,9 @@ name: DocFX
 
 on:
   push:
-    branches: [ master ]
+    branches: [ main ]
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
 
 jobs:
   build:

.github/workflows/dotnet.yml

@@ -2,9 +2,9 @@ name: .NET
 
 on:
   push:
-    branches: [ master ]
+    branches: [ main ]
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
 
 jobs:
   build:

.github/workflows/nightly.yml

@@ -3,7 +3,7 @@ name: Publish Nightly
 on:
   push:
     branches:
-      - master
+      - main
       - develop
 
 jobs:

.github/workflows/sonarcloud.yml

@@ -2,7 +2,7 @@ name: Build
 on:
   push:
     branches:
-      - master
+      - main
   pull_request:
     types: [opened, synchronize, reopened]
 jobs:

.github/workflows/source_validator.yml

@@ -3,7 +3,7 @@ name: Source Validator
 on:
   push:
     branches:
-      - master
+      - main
       - develop
   pull_request:
     types: [opened, synchronize, reopened]