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Fixes#15528
# Description
Fixed `kv set` passing the pipeline input to the closure instead of the
value stored in that key.
# User-Facing Changes
Now `kv set` will pass the value in that key to the closure.
# Tests + Formatting
# After Submitting
After #14906, the test runner was updated to use attributes, along with
the existing `std` modules. However, since that PR was started before
`std-rfc` was in main, it didn't include updates to those tests. Once
#14906 was merged, the `std-rfc` tests no longer ran in CI. This PR
updates the tests accordingly.
