Prevent file upload when folder creation failed

[JammingBen]

Description

We've fixed a bug where files would try to be uploaded if the creation of their respective folder failed beforehands.

Also improved the tests a bit:

• Converted the tests for CreateAndUpload to TypeScript
• Removed the upload helper tests from the component and moved them into a separate test suite

Related Issue

• Fixes web ui continues uploading a folder when receiving a 409 #7957

Screenshots

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests

[ownclouders]

Results for oC10SharingPublic2 https://drone.owncloud.com/owncloud/web/29901/37/1

💥 The acceptance tests failed on retry. Please find the screenshots inside ...

webUISharingPublicExpire-shareByPublicLinkExpiringLinks_feature-L62.png

💥 The oC10SharingPublic2 tests pipeline failed. The build has been cancelled.

[kulmann]

Only a typo in the changelog item, I can change that in another PR when I prepare the next rc tag.

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
1 Code Smell

100.0% Coverage
0.0% Duplication

[ScharfViktor]

re-tested in rc2:

[kulmann]

re-tested in rc2:

It's expected that this shows Unknown error. We can't bring new translation strings to the stable-6.0 branch for technical reasons. The current web master has a more specific error message for this error case.