refactor: remove dependencies from GitHelper to cfg-factory

Define new type `GitCfg`, which specifies minimal cfg (username +
email address, remote-url, credentials) for retrieving and / or
interacting with a git-repository with a remote.

In pipeline-template / code intended to be run within Gardener-CICD,
derive such GitCfgs from GitHubConfig.

This change will ultimately allow creation of GitHelpers also in
environments outside of Gardener-CICD (for example GitHub-Actions).

As GitUtil is used by `release_notes`, which is planned to be re-used in
GitHub-Actions, this is a preliminary step towards that.

cfg_mgmt/util.py

@@ -242,8 +242,9 @@ def rotate_config_element_and_persist_in_cfg_repo(
     '''
     git_helper = gitutil.GitHelper(
         repo=cfg_dir,
-        github_cfg=github_cfg,
-        github_repo_path=github_repo_path,
+        git_cfg=github_cfg.git_cfg(
+            repo_path=github_repo_path,
+        ),
     )
 
     src_file = _local_cfg_file(cfg_element, cfg_factory)
@@ -325,8 +326,9 @@ def process_cfg_queue_and_persist_in_repo(
     '''
     git_helper = gitutil.GitHelper(
         repo=cfg_dir,
-        github_cfg=github_cfg,
-        github_repo_path=github_repo_path,
+        git_cfg=github_cfg.git_cfg(
+            repo_path=github_repo_path,
+        ),
     )
 
     updated_element, processing_successful = cmro.delete_expired_secret(

cli/gardener_ci/_release_notes.py

@@ -78,8 +78,9 @@ def print_release_notes(
 
     git_helper = gitutil.GitHelper.clone_into(
         target_directory=repo_path,
-        github_cfg=github_cfg,
-        github_repo_path=f'{src_access.org_name()}/{src_access.repository_name()}',
+        git_cfg=github_cfg.git_cfg(
+            repo_path=f'{src_access.org_name()}/{src_access.repository_name()}',
+        ),
     )
 
     blocks = release_notes.fetch.fetch_release_notes(

concourse/resources/github.mako

@@ -39,7 +39,7 @@ credentials = github_cfg.credentials()
 disable_tls_validation = not github_cfg.tls_validation()
 token_or_passwd = credentials.auth_token() or credentials.passwd()
 
-preferred_protocol = github_cfg.preferred_protocol()
+preferred_protocol = github_cfg.preferred_protocol
 # repo-specific cfg "wins"
 if (overwrite_preferred_protocol := repo_cfg.preferred_protocol()):
   preferred_protocol = overwrite_preferred_protocol
@@ -117,9 +117,9 @@ credentials = github_cfg.credentials()
   source:
     repo: ${repo_cfg.repo_path()}
     base: ${repo_cfg.branch()}
-% if github_cfg.preferred_protocol() is Protocol.SSH:
+% if github_cfg.preferred_protocol is Protocol.SSH:
     uri: ${github_cfg.ssh_url()}/${repo_cfg.repo_path()}
-% elif github_cfg.preferred_protocol() is Protocol.HTTPS:
+% elif github_cfg.preferred_protocol is Protocol.HTTPS:
     uri: ${github_cfg.http_url()}/${repo_cfg.repo_path()}
 % else:
   <% raise NotImplementedError %>

concourse/steps/draft_release.mako

@@ -97,8 +97,9 @@ github_helper = github.util.GitHubRepositoryHelper(
 )
 git_helper = gitutil.GitHelper(
     repo=repo_dir,
-    github_cfg=github_cfg,
-    github_repo_path='${repo.repo_owner()}/${repo.repo_name()}',
+    git_cfg=github_cfg.git_cfg(
+        repo_path='${repo.repo_owner()}/${repo.repo_name()}',
+    ),
 )
 try:
     release_note_blocks = release_notes.fetch.fetch_draft_release_notes(

concourse/steps/release.mako

@@ -371,8 +371,9 @@ print(f'{version_interface=}')
 
 git_helper = gitutil.GitHelper(
   repo=repo_dir,
-  github_cfg=github_cfg,
-  github_repo_path=f'{repo_owner}/{repo_name}',
+  git_cfg=github_cfg.git_cfg(
+    repo_path=f'{repo_owner}/{repo_name}',
+  ),
 )
 branch = repository_branch
 github_helper = github.util.GitHubRepositoryHelper(

concourse/steps/update_component_deps.mako

@@ -72,8 +72,9 @@ github_cfg=cfg_factory.github(github_cfg_name)
 
 git_helper = gitutil.GitHelper(
     repo=REPO_ROOT,
-    github_cfg=github_cfg,
-    github_repo_path=f'{REPO_OWNER}/{REPO_NAME}',
+    git_cfg=github_cfg.git_cfg(
+        repo_path=f'{REPO_OWNER}/{REPO_NAME}',
+    ),
 )
 merge_policy_configs = [
     concourse.model.traits.update_component_deps.MergePolicyConfig(cfg)

concourse/steps/update_component_deps.py

@@ -692,8 +692,9 @@ def create_release_notes(
         with tempfile.TemporaryDirectory() as temp_dir:
             git_helper = gitutil.GitHelper.clone_into(
                 target_directory=temp_dir,
-                github_cfg=from_github_cfg,
-                github_repo_path=f'{from_repo_owner}/{from_repo_name}'
+                git_cfg=from_github_cfg.git_cfg(
+                    repo_path=f'{from_repo_owner}/{from_repo_name}',
+                ),
             )
             release_note_blocks = release_notes_fetch.fetch_release_notes(
                 component=from_component,