chore(librarian): remove commit body from release notes

[parthea]

The commit body is not needed when creating release notes. It was originally added to workaround googleapis/librarian#2234. As per googleapis/librarian#2234 (comment), we should not include the body in the release notes.

Without the fix in this PR, the changelog for googleapis-common-protos looks like this

## [1.72.0](https://github.com/googleapis/google-cloud-python/compare/googleapis-common-protos-v1.71.0...googleapis-common-protos-v1.72.0) (2025-11-05)


### Features

* add common_resources.proto (#14851) This PR depends on
https://github.com/googleapis/google-cloud-python/pull/14850
`google/cloud` was not listed as an api path for
`googleapis-common-protos` for code was not being generated for
https://github.com/googleapis/googleapis/blob/master/google/cloud/extended_operations.proto
and
https://github.com/googleapis/googleapis/blob/master/google/cloud/common_resources.proto ([e4e0e2a93c3db14324c1d9f799283ffe4f2bec09](https://github.com/googleapis/google-cloud-python/commit/e4e0e2a93c3db14324c1d9f799283ffe4f2bec09))
* add field api_version to message ServiceForTransport (#14843) This PR was created locally. The reason that this could not be automated
is that the current directory structure
[gapic/metadata](https://github.com/googleapis/googleapis/tree/master/gapic/metadata)
doesn't align with the protobuf package name
[google.gapic.metadata](https://github.com/googleapis/googleapis/blob/53af3b727f84acc34e31c23f3b6e7b8aa4b7e837/gapic/metadata/gapic_metadata.proto#L18).
The expected directory structure for `google.gapic.metadata` is
`google/gapic/metadata`.
In the `googleapis-common-protos` package, the `gencode` is in the
expected location ([81812fde4f1e43d568d53d6a993cf423b38d6728](https://github.com/googleapis/google-cloud-python/commit/81812fde4f1e43d568d53d6a993cf423b38d6728))

With the fix, the changelog for googleapis-common-protos looks like this

## [1.72.0](https://github.com/googleapis/google-cloud-python/compare/googleapis-common-protos-v1.71.0...googleapis-common-protos-v1.72.0) (2025-11-05)


### Features

* add common_resources.proto (#14851) ([e4e0e2a93c3db14324c1d9f799283ffe4f2bec09](https://github.com/googleapis/google-cloud-python/commit/e4e0e2a93c3db14324c1d9f799283ffe4f2bec09))
* add field api_version to message ServiceForTransport (#14843) ([81812fde4f1e43d568d53d6a993cf423b38d6728](https://github.com/googleapis/google-cloud-python/commit/81812fde4f1e43d568d53d6a993cf423b38d6728))