Fix broken mc anonymous get/get-json

[subnix]

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Description

mc anonymous get/get-json have been broken by PR #4745, because it tries to guess an operation and fails before finding one. So we can avoid this by explicit operation handling.

How to test this PR?

mc anonymous get [target]
mc anonymous get-json [target]

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Optimization (provides speedup with no functional changes)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• Fixes a regression (PR set-json to fail on custom policies without .json #4745)
• Unit tests added/updated
• Internal documentation updated
• Create a documentation update request here

[subnix]

Oh, now I see fix f78f391, but it hasn't been completely fixed. It doesn't work if file/directory named TARGET exists.

mkdir -p play/upload
mc anonymous get play/upload