Fix gradient clipping

[alsrgv]

Before submitting

• Was this discussed/approved via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure to update the docs?
• Did you write any new necessary tests?
• If you made a notable change (that affects users), did you update the CHANGELOG?

What does this PR do?

This PR fixes broken gradient clipping.

PR review

Anyone in the community is free to review the PR once the tests have passed.
If we didn't discuss your PR in Github issues there's a high chance it will not be merged.

Did you have fun?

Yep :-)

[codecov]

Codecov Report

Merging #1438 into master will not change coverage by %.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #1438   +/-   ##
======================================
  Coverage      92%     92%           
======================================
  Files          66      66           
  Lines        3509    3509           
======================================
  Hits         3213    3213           
  Misses        296     296           

[alsrgv]

Thanks for a quick merge!