Inject username and password via new DSL

Author: marcphilipp

Diff for: .github/workflows/main.yml

@@ -127,4 +127,5 @@ jobs:
           gitPublishPush \
           -Dscan.tag.Documentation
       env:
-        GRGIT_USER: ${{ secrets.GH_TOKEN }}
+        GIT_USERNAME: git
+        GIT_PASSWORD: ${{ secrets.GH_TOKEN }}

Diff for: documentation/documentation.gradle.kts

@@ -109,6 +109,9 @@ gitPublish {
 	sign = false
 	fetchDepth = 1
 
+	username = providers.environmentVariable("GIT_USERNAME")
+	password = providers.environmentVariable("GIT_PASSWORD")
+
 	contents {
 		from(docsDir)
 		into("docs")