submodule(build): update to a6e25af

[jvrplmlmn]

Description of your changes

When working on https://github.com/crossplane-contrib/provider-sql/pull/149, we found e2e failures.

In this PR I'm updating the build submodule to the latest reference mentioned in https://github.com/crossplane/provider-template

This PR results now in a valid build, and want to discard that the issue that we are encountering is due to some obsolete dependency, or if instead it is coming from the code changes.

I have:

• [x] Read and followed Crossplane's contribution process.
• [x] Run make reviewable to ensure this PR is ready for review.

How has this code been tested

Verified that the CI gives us a passing build.

[jvrplmlmn]

This was not needed for #149, so going to close it for now.