Add configuration-template to well known xpkg init templates

[jbw976]

Description of your changes

This PR adds the new https://github.com/crossplane/configuration-template repo that @lsviben created to the list of well known template repos used by xpkg init. Follows the same pattern of #5249.

Fixes #5014

Testing Details:

The changes in this PR were built locally with make and tested with xpkg init using the new well known name from this PR, which shows the configuration-template repo being cloned locally and the NOTES.txt file being displayed:

❯ ./_output/bin/darwin_arm64/crank beta xpkg init my-config configuration-template -d config-template-test
Initialized package "my-config" in directory "/Users/jared/dev/go/src/github.com/crossplane/crossplane/config-template-test" from https://github.com/crossplane/configuration-template/tree/4bb38f77e13c8b1ed741cb3d8ae0cc8ba3eda960 (main)

A template for writing a Configuration (https://docs.crossplane.io/v1.14/concepts/packages).

To use this template:
1. Replace the name, metadata in crossplane.yaml to reflect your Configuration.
2. Add dependencies in crossplane.yaml.
3. Update the sample CompositeResourceDefinition and Composition in the `apis/`
   directory to reflect the API you're designing for your platform, and optionally add more if needed.
4. Add/Update examples in the `examples/` directory.
5. Update the `README.md`, to be about your Configuration!

To build and push your Configuration to a registry, run the following commands
using the Crossplane CLI:

`crossplane xpkg build`
(Optionally) `crossplane xpkg login`
`crossplane xpkg push your-org/your-repo:v1.0.0`

Check the README.md for more information and have fun building your Configuration!

The expected content of the https://github.com/crossplane/configuration-template repo appears in the specified directory:

❯ ls config-template-test
NOTES.txt       README.md       apis            crossplane.yaml examples

I have:

• Read and followed Crossplane's contribution process.
• Run make reviewable to ensure this PR is ready for review.
• Added or updated unit tests.
• Added or updated e2e tests.
• Linked a PR or a docs tracking issue to document this change.
• Added backport release-x.y labels to auto-backport this PR.

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[github-actions]

Successfully created backport PR for release-1.15:

• [Backport release-1.15] Add configuration-template to well known xpkg init templates #5390