feat: Remove code suggestions request states from status bar

Description

This MR removes code suggestions request state from status bar. Code suggestion request states (loading, error) are only visible through gutter icon.

Related Issues

Resolves #1444 (closed)

How has this been tested?

• Locally run VS Code extension
• Go to a supported language file
• Trigger code suggestion and check
  • status bar icon doesn't change
  • gutter icon changes to loading icon as code suggestion is loading.
• Simulate code suggestion error state by calling this.#stateManager.setError(true) in https://gitlab.com/gitlab-org/gitlab-vscode-extension/-/blob/main/src/common/language_server/language_client_middleware.ts#L56
• Trigger code suggestion and check
  • status bar icon doesn't change
  • gutter icon changes to error icon

Isolate Code Suggestion Request State from Status bar.mov

Screenshots (if appropriate)

What CHANGELOG entry will this MR create?

• fix: Bug fix fixes - a user-facing issue in production - included in changelog
• feature: New feature - a user-facing change which adds functionality - included in changelog
• BREAKING CHANGE: (fix or feature that would cause existing functionality to change) - should bump major version, mentioned in the changelog
• None - other non-user-facing changes

Closes #1444 (closed)