Fix e2e tests

[cstns]

Description

OS tests caused by a miraculous series of events that managed the invitation spec can reject an invitation to a new team test to click on the notification's checkbox selector, missing the notification body that actually redirected the user to the invitations page required for the tests to pass.

The following OS tests were failing because of tight coupling between tests, and member count expectations were failing.

Why the click event landed on the checkbox on GH action runs and not locally is beyond meat this point, given that we're forcing the same screen resolution and browser for both gh actions and local runs.

The OS tests passing uncovered a real bug with blueprint deployment in that both blueprint and flows were being to through the http call on creation causing a backend check to fail. I also addressed that here.

Related Issue(s)

fixes e2e tests for #6137

Checklist

• I have read the contribution guidelines
• Suitable unit/system level tests have been added and they pass
• Documentation has been updated
  • Upgrade instructions
  • Configuration details
  • Concepts
• Changes flowforge.yml?
  • Issue/PR raised on FlowFuse/helm to update ConfigMap Template
  • Issue/PR raised on FlowFuse/CloudProject to update values for Staging/Production
• Link to Changelog Entry PR, or note why one is not needed.

Labels

• Includes a DB migration? -> add the area:migration label

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 76.80%. Comparing base (1cca27e) to head (9c56ca6).
⚠️ Report is 4 commits behind head on multi-step-form-import-flows.

Additional details and impacted files

@@                      Coverage Diff                      @@
##           multi-step-form-import-flows    #6151   +/-   ##
=============================================================
  Coverage                         76.80%   76.80%           
=============================================================
  Files                               381      381           
  Lines                             19315    19315           
  Branches                           4651     4651           
=============================================================
  Hits                              14835    14835           
  Misses                             4480     4480           

Flag	Coverage Δ
backend	76.80% <ø> (ø)

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