Decode square brackets with "queryToObject" [RUN ALL RSPEC] [RUN AS-IF-FOSS]

What does this MR do?

Fix for #336895 (closed)

This change ensure that URL-encoded square brackets are decoded by "queryToObject" when such encoding is used in the URL.

Prevents edge cases in which clients send encoded square brackets to define arrays in their URL parameters.

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Related to #336895 (closed)