test(fixtures): Ease testing just one fixture

[Vaelatern]

Description

$ ./test-fixtures.sh
[ok] test-duplicate-file-upload
[ok] test-expiring-file-upload
[ok] test-file-delete
[ok] test-file-upload
[ok] test-file-upload-override-filename
[ok] test-file-upload-same-filename
[ok] test-filename-replace
....
[ok] test-server-payload-limit
[ok] test-url-encode
[ok] test-url-upload
[ok] test-version-not-exposed
$

And it could be:

$ ./test-fixtures.sh
... everything from above without arguments....
$ ./test-fixtures.sh test-server-auth-multiple-tokens test-server-auth test-url-encode
[ok] test-server-auth-multiple-tokens
[ok] test-server-auth
[ok] test-url-encode
$

Motivation and Context

I was running tests for #373 and it was taking long enough to warrant a fix.

How Has This Been Tested?

Please see description for example run.

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)
• Documentation (no code change)
• Refactor (refactoring production code)
• Other: Tooling and developer joy.

Checklist:

• My code follows the code style of this project.
• I have updated the documentation accordingly.
• I have formatted the code with rustfmt.
• I checked the lints with clippy.
• I have added tests to cover my changes.
• All new and existing tests passed.

[tessus]

LGTM

[orhun]

LGTM, merging with some nits :)