Add warning for non multi env commands

[EvilGenius13]

WHY are these changes introduced?

Fixes #0000

WHAT is this pull request doing?

How to test your changes?

Post-release steps

Measuring impact

How do we know this change was effective? Please choose one:

• n/a - this doesn't need measurement, e.g. a linting rule or a bug-fix
• Existing analytics will cater for this addition
• PR includes analytics changes to measure impact

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes

[github-actions]

Coverage report

St.❔	Category	Percentage	Covered / Total
🟡	Statements	78.32% (-0.02% 🔻)	12543/16016
🟡	Branches	72.49% (+0.02% 🔼)	6106/8423
🟡	Functions	78.47% (-0.02% 🔻)	3272/4170
🟡	Lines	78.76% (-0.02% 🔻)	11868/15069

Show files with reduced coverage 🔻

St.❔	File	Statements	Branches	Functions	Lines
🟢	... / handlers.ts	97.3% (+5.36% 🔼)	66.67% (-1.19% 🔻)	100% (+10.53% 🔼)	97.22% (+5.42% 🔼)
🟢	... / Dev.tsx	90.59% (-2.35% 🔻)	75% (-1.79% 🔻)	86.36% (-4.55% 🔻)	92.5% (-1.25% 🔻)
🔴	... / theme-command.ts	38.46% (-4.93% 🔻)	15.38% (-3.85% 🔻)	40%	41.67% (-5.27% 🔻)

Test suite run success

2902 tests passing in 1259 suites.

Report generated by 🧪jest coverage report action from 90de078