don't allow submit defocus on invalid textbox input

[jkrumbiegel]

Description

Fixes #2037

On submitting an invalid textbox, the text shouldn't defocus which looks like submitting it worked.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist

• Added an entry in NEWS.md (for new features and breaking changes)

[MakieBot]

Compile Times benchmark

Note, that these numbers may fluctuate on the CI servers, so take them with a grain of salt.

using time

master:  9.10 < 9.15 > 9.20, 0.03+-
pr:      9.12 < 9.15 > 9.19, 0.03+-
speedup: 1.00 < 1.00 > 1.01, 0.00+-
median:  +0.10% => invariant

This PR does not change the using time.

ttfp time

master   24.24 < 24.29 > 24.57, 0.11+-
pr       24.28 < 24.38 > 24.44, 0.06+-
speedup: 0.99 < 1.00 > 1.01, 0.00+-
median:  +0.35% => invariant

This PR does not change the ttfp time.