Add more informative error messages to context commands

[craddm]

✅ Checklist

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🚦 Depends on

N/A

⤴️ Summary

Adds more informative messages when users try to use context functions without first having created a context file.

Catches that user is not logged in when trying to create or teardown context infrastructure.

WIP: Catch that no context infrastructure is deployed

🌂 Related issues

Closes #1897
Closes #1899

🔬 Tests

tested locally

[JimMadge]

@craddm Is this ready for review?

[craddm]

Pretty much - some tests failing as the commands now error when not logged in with Azure CLI. Do we know how to handle that?

[JimMadge]

@craddm Shall I pick up this one?

[github-actions]

Coverage report

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
data_safe_haven/commands
context.py
data_safe_haven/context_infrastructure
infrastructure.py
data_safe_haven/exceptions
__init__.py
data_safe_haven/external/api
azure_api.py					143, 183, 262, 299, 333, 417, 475, 520, 541, 581, 625, 653, 690, 728, 772, 829, 845-849, 925, 953, 1006, 1038
data_safe_haven/external/interface
azure_authenticator.py					67-68
Project Total

This report was generated by python-coverage-comment-action

[jemrobinson]

Mostly looks good. A couple of questions but nothing serious.

[jemrobinson]

@JimMadge : are you still responsible for this PR? Happy to take it over if you're busy.

[jemrobinson]

LGTM

Stale