fix redudant message in unexpected error

[VincentKempers]

Description

I couldn't really reproduce the error in this unexpected-error.vue, but this is about the message itself.

The message in the unexpected-error.vue was redundant as the code and error message are already shown.

Fixes #14972

Type of Change

• Bugfix
• Improvement
• New Feature
• Refactor / codestyle updates
• Other, please describe:

Requirements Checklist

• New / updated tests are included
• All tests are passing locally
• Performed a self-review of the submitted code

If adding a new feature:

• Documentation was added/updated

[azrikahar]

The message in the unexpected-error.vue was redundant as the code and error message are already shown.

Hi! Can you share what was the scenario in your test which still yields error message in the dialog?

Been noticing it showing a blank dialog for Unexpected Error now (not sure about other errors yet), which seems abit odd.

	Before	After
Dialog shown
Value in store

[rijkvanzanten]

@azrikahar message was rendered as the second line in that card, and then rendered again in the v-error component as part of the error. The idea of this pr was to remove the line "in the middle" between the title and the v-error component. That being said, the v-error component itself should still be rendered, so that's a new bug