Pin generic plink2 build for the HWE job

[joshuamschmidt]

Purpose

plink2 a.7.3 AVX2 builds hang in an infinite loop at 'Computing chrX Hardy-Weinberg p-values' on the 2660-sample OurDNA aggregate (COH15003); the a.6.33 AVX2 build segfaulted at the same point. The generic x86_64 build of a.7.3 completes the identical command on the identical data in about 20 seconds (verified locally against the production pgen). Disabling the midp and keep-fewhet modifiers does not help, so the trigger is the AVX2 code path itself.

Proposed Changes

• Set PLINK2_FORCE_VARIANT=generic on the SnpQcReport HWE job. The override is added to the plink image wrapper in Add PLINK2_FORCE_VARIANT override to the plink wrapper images#323 and requires plink image tag 1.9-20250819-PLINK-2.0-20260808-2 or later.
• Remove once the upstream AVX2 bug is fixed; an upstream issue is being raised.

Testing

• Production batches 1135770 (segfault, a6 AVX2), 1135797 and 1135810 (hangs, a7 AVX2 with and without midp).
• Same command and data with the generic a7 build completes locally: 1,731,312 of 1,732,809 variants pass.

[Alexander-Stuckey]

Looks good to me