Auto merge of #24818 - gterzian:fix_panic_on_finish_load, r=jdm

Prevent panic on layout send in finish-load

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Do not run the finish load steps if the pipeline has been discarded by the time the parser finishes.

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- [ ] `./mach build -d` does not report any errors
- [ ] `./mach test-tidy` does not report any errors
- [ ] These changes fix #22955 (GitHub issue number if applicable)

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- [ ] There are tests for these changes OR
- [ ] These changes do not require tests because ___

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0 files changed, 0 insertions, 0 deletions