Fix maps/lists with sensitive members not redacted (#3765)

## Motivation and Context
<!--- Why is this change required? What problem does it solve? -->
<!--- If it fixes an open issue, please link to the issue here -->
Lists and maps with sensitive members were not being properly redacted.
Closes https://github.com/smithy-lang/smithy-rs/issues/3757

## Description
<!--- Describe your changes in detail -->
Updated `Shape.shouldRedact` method to properly check for list and map
shapes with sensitive members. Also updated the test definition so it
would actually run since previously the test code was generated in a
nested function inside a no-op function and never run.

## Testing
<!--- Please describe in detail how you tested your changes -->
<!--- Include details of your testing environment, and the tests you ran
to -->
<!--- see how your change affects other areas of the code, etc. -->
Added test cases for lists with sensitive members, maps with sensitive
keys, and maps with sensitive values.

## Checklist
<!--- If a checkbox below is not applicable, then please DELETE it
rather than leaving it unchecked -->
- [x] I have updated `CHANGELOG.next.toml` if I made changes to the
smithy-rs codegen or runtime crates


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