ci: combine build and deploy web workflows

[staceybeard]

By submitting this merge request, I confirm the following:

• The merge request title follows the conventional commits convention (see Backend project's README.md)
  • feat: minor app version will be incremented.
  • fix, deps, perf: patch app version will be incremented.
  • chore, ci, etc.: app version will not be incremented.
  • See semantic-release/commit-analyzer
    for complete set of rules.

Changes

Combined the build and deployment workflows for the web app, to match the combined workflow for build and deployment of the mobile app.

• Replaced github.ref with github.ref_name.
• Removed unnecessary capitalization of the ENVIRONMENT variable, since GitHub Actions variables are case-insensitive.

Dependencies

• Listener: N/A