REST API - split troubleshooting content to new page

doc/api/admin/token.md

doc/api/code_suggestions.md

doc/api/group_markdown_uploads.md

doc/api/groups.md

doc/api/issues.md

doc/api/member_roles.md

doc/api/merge_requests.md

doc/api/pages.md

doc/api/project_container_registry_protection_rules.md

doc/api/project_job_token_scopes.md

doc/api/project_markdown_uploads.md

doc/api/project_packages_protection_rules.md

doc/api/releases/index.md

doc/api/remote_mirrors.md

doc/api/rest/index.md

doc/api/rest/troubleshooting.md

doc/api/saml.md

doc/api/scim.md

doc/api/search_admin.md

doc/api/web_commits.md