Adds link to workshop page for the missing mod on error: workshop mod not found

[Crowdedlight]

Adds a direct link in the error message that a workshop mod is not found. Makes it easier to quickly open and subscribe to the missing mod.
Suggested by OverlordZorn on discord.

Before:

After:

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 68.8%. Comparing base (21b2b2e) to head (8a768b2).
Report is 2 commits behind head on main.

Files	Patch %	Lines
...mands/launch/error/bcle3_workshop_mod_not_found.rs	0.0%	1 Missing ⚠️

Additional details and impacted files

Files	Coverage Δ
...mands/launch/error/bcle3_workshop_mod_not_found.rs	0.0% <0.0%> (ø)

... and 7 files with indirect coverage changes