[tests-only] extend API test coverage for content-disposition header

[saw-jan]

Description

Added API test to check Content-Disposition header for a file containing comma in its name

Related Issue

Coverage for:

• Cannot edit or download file with comma on Web #8361
• fix content-dispostion header in dav cs3org/reva#4498

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

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 only (no source changes)

Checklist:- [ ] Code changes

• Unit tests added
• Acceptance tests added
• Documentation ticket raised:

[sonarcloud]

Quality Gate passed

Kudos, no new issues were introduced!

0 New issues
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[phil-davis]

@saw-jan we can merge this.
But it would also be nice to know what happens if the file name contains single or double quotes. Those will involve some sort of escaping in the Content-Disposition header, which could easily cause problems.
So some more scenario examples could be added in another PR.