CI: add merge_group to enable merge queue (#983)

Author: mj-will

.github/workflows/basic-install.yml

@@ -5,6 +5,7 @@ on:
     branches: [ "main" ]
   pull_request:
     branches: [ "main" ]
+  merge_group:
   release:
     types:
       - published

.github/workflows/pages.yml

@@ -11,6 +11,7 @@ on:
     branches: [ "main" ]
   pull_request:
     branches: [ "main" ]
+  merge_group:
   release:
     types:
       - published

.github/workflows/pre-commit.yml

@@ -5,6 +5,7 @@ on:
     branches: [ "main" ]
   pull_request:
     branches: [ "main" ]
+  merge_group:
   release:
     types:
       - published

.github/workflows/unit-tests.yml

@@ -8,6 +8,7 @@ on:
     branches: [ "main" ]
   pull_request:
     branches: [ "main" ]
+  merge_group:
   release:
     types:
       - published