[s3proxy] integration test for allowed characters

[norling]

We should have integration tests to show that we allow unicode characters, and disallow special restricted characters. The test does not have to pass to close this card (that is - you do not have to fix any issues that shows up).

The tests should be run locally.

Example of allowed filenames:

• 🍫 ⋆ 🍡 🎀 𝒻𝒶𝓃𝒸𝓎 𝓂𝑒𝒹𝒾𝒸𝒶𝓁 𝒾𝓂𝒶𝑔𝑒 🎀 🍡 ⋆ 🍫.dcm
• ņọŗmal_meḑĩćąl_ĭmagȩ.dcm

Examples of disallowed filenames: (disallowed characters are \/:*?"<>| + control characters)

• image\file.dcm
• genomic:file.dcm

[norling]

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[MalinAhlberg]

static tests exist, check if we need more