Bump gcm from v2.6.0 > v2.6.1

[kzu]

Security Fixes:

• CVE-2024-50338
  • Do not treat the lone carriage-return character (CR, \r) as a line terminator in the credential helper protocol

Changes:

• Fix Linux build scripts (fix wrong bash if-else syntax git-ecosystem/git-credential-manager#1752)
• Documentation fix for broken links (docs: update Secret Service links git-ecosystem/git-credential-manager#1722)
• Permit use of HTTP (not-S) remotes for providers via config (Add control over use of unsafe remotes git-ecosystem/git-credential-manager#1721)
• Omit the client secret for GitLab (Omit GitLab client secret git-ecosystem/git-credential-manager#1538)
• Various workflow action updates (build(deps): bump lycheeverse/lychee-action from 1.9.3 to 2.0.0 git-ecosystem/git-credential-manager#1725, build(deps): bump lycheeverse/lychee-action from 2.0.0 to 2.0.2 git-ecosystem/git-credential-manager#1738, build(deps): bump actions/setup-dotnet from 4.0.1 to 4.1.0 git-ecosystem/git-credential-manager#1751, build(deps): bump azure/trusted-signing-action from 0.4.0 to 0.5.0 git-ecosystem/git-credential-manager#1750)
• Fix CentOS install from source workflow (ci: move to "more official" tgagor/centos git-ecosystem/git-credential-manager#1746)
• Add Mariner and Arch Linux distribution validation builds (ci: add Mariner and Arch Linux git-ecosystem/git-credential-manager#1747)
• Add no-op credential storage option (Add no-op credential storage option git-ecosystem/git-credential-manager#1740)