We are still running some specs twice: with and without gitaly

Some of the specs still use the :disable_gitaly tag and then run shared examples twice:

We should get rid of the duplicate specs.

File: spec/models/repository_spec.rb
418:59:    context 'when Gitaly list_commits_by_oid is enabled', :disable_gitaly do
1442:55:    context 'when Gitaly revert feature is disabled', :disable_gitaly do
1498:60:    context 'when Gitaly cherry_pick feature is disabled', :disable_gitaly do

File: spec/models/wiki_page_spec.rb
412:40:    context 'when Gitaly is disabled', :disable_gitaly do
562:65:    context 'when Gitaly wiki_page_formatted_data is disabled', :disable_gitaly do

File: spec/models/merge_request_spec.rb
73:59:    context 'when Gitaly squash_in_progress is disabled', :disable_gitaly do
2557:58:    context 'when Gitaly rebase_in_progress is enabled', :disable_gitaly do

File: spec/support/gitaly.rb
3:25:    if example.metadata[:disable_gitaly]

File: spec/lib/gitlab/diff/file_collection/merge_request_diff_spec.rb
46:35:  context 'with Gitaly disabled', :disable_gitaly do

File: spec/lib/gitlab/git/tag_spec.rb
58:61:    context 'when Gitaly tag_messages feature is disabled', :disable_gitaly do

File: spec/lib/gitlab/git/commit_spec.rb
597:64:    context 'when Gitaly commit_messages feature is disabled', :disable_gitaly do