Hotfix/matriculation validation

[tobias-wiese]

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Remove this, if this PR is not to main!

Version to release: v0.9.0-hotfix.1

Merging this pull request will automatically:

• create a tag using the version in our package.json
• publish a release using this tag, referencing the CHANGELOG.md
• publish the release on dockerhub using the version of our package.json

Please fill out the following checklist:

• The version of the package.json is different to every other tag in this repository
• The CHANGELOG.md contains all changes (bugfixes, features, dependency updates, ...) for this release

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Description

• Fixes issue No error shown when trying to add a FoS for a semester earlier than birthdate #541
• Fixes issue Disconnect matriculation changes from hasChange computed value #542
• Closes No error shown when trying to add a FoS for a semester earlier than birthdate #541 Disconnect matriculation changes from hasChange computed value #542

Reason for this PR

• see No error shown when trying to add a FoS for a semester earlier than birthdate #541 Disconnect matriculation changes from hasChange computed value #542

Changes in this PR

• adapt error bag to enable searching for substrings (as we get errors in form of e.g. matriculations[0].semesters[0])
• remove v-modelled immatriculationChanged variable
• change desired error type to HLUnprocessableEntity

Type of change (remove all that don't apply)

• Hotfix

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Manually tested all use cases this could alter

Test Configuration:

• OS: Windows Mac Linux

• Browser: Firefox Chrome Safari Chromium

• Frontend: (remove all that don't apply)

  • Development build

• Backend: (remove all that don't apply)

  • deployed development build

Checklist: (remove all that don't apply)

• I added corresponding E2E tests (especially for bugfixes)
• I have performed a self-review of my own code
• My changes generate no new linting warnings or console warnings
• I have updated the package.json version if this is a new release candidate
• I have updated the CHANGELOG.md to include any changes made in this PR (add WIP to the top, if there is none already)