enh(file) improve Diff output when a file is changed

[dduportal]

Fix #369

Example of output:

pdateGroovyCode
----------------

**Dry Run enabled**

✔ File content for "/var/folders/2s/09szbrgn22l2tcvxz1_k34g40000gn/T/updatecli/jenkins-infra/pipeline-library/vars/buildDockerAndPublishImage.groovy", updated. 

--- /var/folders/2s/09szbrgn22l2tcvxz1_k34g40000gn/T/updatecli/jenkins-infra/pipeline-library/vars/buildDockerAndPublishImage.groovy
+++ /var/folders/2s/09szbrgn22l2tcvxz1_k34g40000gn/T/updatecli/jenkins-infra/pipeline-library/vars/buildDockerAndPublishImage.groovy
@@ -33,7 +33,7 @@
       ),
       containerTemplate(
         name: 'next-version',
-        image: config.nextVersionImage ?: 'ghcr.io/jenkins-x/jx-release-version:2.4.13',
+        image: config.nextVersionImage ?: 'ghcr.io/jenkins-x/jx-release-version:2.5.1',
         command: 'cat',
         ttyEnabled: true,
         resourceRequestCpu: '200m',
         ```

## Test

To test this pull request, you can run the following commands:

```shell
cp <to_package_directory>
go test

Additional Information

Tradeoff

Potential improvement

[olblak]

I love the output improvement, and it could probably be applied to other places as well