Fix keyword filtering in listBackupOfferings API

[chezsan770]

The keyword parameter was already being passed with wildcard values,
but the search criteria used an EQ operator, causing filtering to fail.
This change updates the operator to LIKE so keyword-based searches
work as expected.

[boring-cyborg]

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[Pearl1594]

I believe this has already been addressed by: #12480

[chezsan770]

Thanks for pointing this out.
I checked #12480 and it indeed addresses the same issue.
Closing this PR to avoid duplication.

[shwstppr]

Closing based on the comments from author @chezsan770