Improve UI success/error while adding storages

[AlexAndBear]

Description

• While adding or changing an external storage, a success/error notification will be shown
• Added cursor->pointer to the status item, due a click results in a recheck

Related Issue

• Fixes https://github.com/owncloud/enterprise/issues/4302

Motivation and Context

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Database schema changes (next release will require increase of minor version instead of patch)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:
• Changelog item, see TEMPLATE

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[JammingBen]

Looks good to me

[phil-davis]

A typo in the changelog text. Sad to have to run all that CI again just for this.

[AlexAndBear]

Can be merged after tech demo

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[jvillafanez]

I see a potential problem. Let's assume the following setup:

1. SMB / WND with login credentials (shouldn't matter whether they're saved in session or in DB)
2. Both ownCloud and the storage are connected to the windows' AD. This means that only the AD users will be able to access to the external storage. In particular, the admin won't be able to access

Normally, the connectivity check is done using the admin account. If the admin cannot access to the external storage, we assume there is a problem with the setup. However, in the setup above, the problem is that there is no admin in the AD. Using a valid AD account instead of the ownCloud's admin would show a green light instead.

I'm a bit worried that the error message will make more noise even though the setup itself could be fine. A softer message could be better, such as "The current ownCloud's user (in case there are multiple admins) can't access to the external storage. In some scenarios, this could be ok, but please, recheck the configuration"

[AlexAndBear]

@jvillafanez Edgy case but a good objection, maybe we could show this 'soften message' only if there is an error with the SMB/WND configuration?

[jvillafanez]

Technically, it can happen with any storage. I guess the setup above is kind of expected for SMB/WND, so this flaw is more visible there.
For the case of SFTP, for example, the same could also happen, although it's likely easier to create an account for the admin inside the SFTP storage

[AlexAndBear]

@pmaier1 @cdamken @hodyroff @micbar
Please take @jvillafanez comment into account for the tech demo meeting

[AlexAndBear]

@jvillafanez as discussed with PM we will still show this message but enter a hint in the docs

[mmattel]

as discussed with PM we will still show this message but enter a hint in the docs

@janackermann Please create a docs issue, else this will be gone and lost