fix: allow GitLab edits to create & switch across new branches and source files

[cuserox]

Why does this PR exist?

Closes #3076

Users were experiencing errors when switching from single / multi files or referencing new branches. Similar to ADO: #3071

What does this pull request do?

• Adds checks in the GitLab client to create the necessary branch / file / directory before pushing
• Creates the new branch based on the currently selected one in the plugin
• Fallback to the previous state if the user doesn't push changes

Testing this change

• Set up GitLab as a remote provider
• Change some settings by going to: Settings ---> Edit your Sync provider

• Edit the details by:
  • Switching from a single file (tokens.json) to a multifile setup (themes)
  • Switching branches
• Pushing to the remote should work as expected

[changeset-bot]

🦋 Changeset detected

Latest commit: 21d9165

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@tokens-studio/figma-plugin	Patch

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[github-actions]

⤵️ 📦 ✨ The artifact was successfully created! Want to test it? Download it here 👀 🎁

[github-actions]

Commit SHA:f142c68ef9a4f24bf595e7e2b22892eaa2c9a323

Test coverage results 🧪

Code coverage diff between base branch:main and head branch: fix/3076-gitlab-multifile-creation 

Status	File	% Stmts	% Branch	% Funcs	% Lines
🔴	total	67.92 (0.01)	58.54 (-0.05)	64.56 (0)	68.32 (0.01)
🔴	packages/tokens-studio-for-figma/src/app/store/providers/gitlab/gitlab.tsx	95.55 (-0.54)	81.81 (-4.55)	100 (0)	96.87 (-0.65)
🟢	packages/tokens-studio-for-figma/src/storage/GitlabTokenStorage.ts	60 (0.55)	47.77 (0.21)	52 (0)	60.37 (0.58)

[github-actions]

Commit SHA:f142c68ef9a4f24bf595e7e2b22892eaa2c9a323
Current PR reduces the test coverage percentage by 1 for some tests

[macintoshhelper]

LGTM

[rbosker]

tested and worked properly!