Fixed jit_freeze_discard in hdrfilm

[DoeringChristian]

Description

This PR adds a jit_freeze_discard call to the hdrfilm, which ensures that the first recording of a rendering function is discarded, as it is not possible to re-create the imageblock when replaying the frozen function.

Fixes # (issue)

Testing

Checklist

• My code follows the style guidelines of this project
• My changes generate no new warnings
• My code also compiles for cuda_* and llvm_* variants. If you can't test this, please leave below
• I have commented my code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I cleaned the commit history and removed any "Merge" commits
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