Don't show the password input if the username is not correctly validated

[jredrejo]

Summary

Password input text is not shown until the username is validated

Reviewer guidance

Pressing next without adding an username (or using an invalid username) does not show the password input screen

References

Closes #7093

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• Automated test coverage is satisfactory
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[codecov]

Codecov Report

Merging #7102 into release-v0.14.x will decrease coverage by 0.03%.
The diff coverage is 20.00%.

Impacted Files	Coverage Δ
...libri/plugins/user/assets/src/views/SignInPage.vue	33.33% <20.00%> (-1.09%)	⬇️
kolibri/core/tasks/utils.py	89.65% <0.00%> (-3.45%)	⬇️
kolibri/core/content/utils/channel_import.py	88.48% <0.00%> (-0.57%)	⬇️
kolibri/plugins/device/assets/src/constants.js	100.00% <0.00%> (ø)
kolibri/core/assets/src/views/AppError/index.vue	68.75% <0.00%> (ø)
...i/plugins/device/assets/src/views/DeviceTopNav.vue	100.00% <0.00%> (ø)
...i/plugins/learn/assets/src/modules/search/index.js	0.00% <0.00%> (ø)
...plugins/learn/assets/src/modules/search/actions.js	0.00% <0.00%> (ø)
...ns/setup_wizard/assets/src/views/PersonalSetup.vue	0.00% <0.00%> (ø)
... and 11 more

[nucleogenesis]

Just the issue noted below:

[nucleogenesis]

If you click "next" before entering anything and then start typing, it transitions to the password form after 1 character because that's all it takes to make username valid.

I'd suggest also changing setSelectedListUser to not save the selectedListUser if there is no username given.

[jredrejo]

@nucleogenesis Done

[indirectlylit]

We need to show some user feedback that the username field is required:

[radinamatic]

It used to be there on 0.13

[jredrejo]

We need to show some user feedback that the username field is required:

@indirectlylit done. I hadn't notice the issue because pressing Enter the validation error appeared. Now it appears when clicking on the next button too.

[jonboiser]

looks good to me!

issue was fixed