Update develocity-injection init script to v1.2

[bot-githubaction]

Updates the develocity-injection init script to the latest reference script content
from https://github.com/gradle/develocity-ci-injection.

[alextu]

@bigdaz the Gradle plugin version is configurable by the user, which means it can be set to an older version compatible with Gradle < 5. If we formally constrain the versions in the init script, then we need to accommodate the CI integrations to validate the DV Gradle plugin version configured by users.

[bigdaz]

The init-script will automatically apply com.gradle.build-scan:1.16 for any Gradle version older than 5.0. So there's never a reason to configure this version for injection.

The reason for the new check DV-plugin version check is that we don't test the init-script for a wider range of configured DV plugin versions, and that older versions are largely broken with the CCUD Gradle plugin.

But I see your point about validating the input in the UI. We already had a check in the init-script that CCUD Gradle plugin version is > 1.7. Do we validate that in the UI now?