Reapply Revert "ref: upgrade pytest (#81135)" (#81643)

we suspect this may have increased error rates in CI -- it appears to
have been accidentally upgrade in #81048

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requirements-dev-frozen.txt

@@ -146,7 +146,7 @@ pyflakes==3.2.0
 pyjwt==2.4.0
 pymemcache==4.0.0
 pysocks==1.7.1
-pytest==8.3.3
+pytest==8.1.2
 pytest-cov==4.0.0
 pytest-django==4.9.0
 pytest-fail-slow==0.3.0

requirements-dev.txt

@@ -10,7 +10,7 @@ time-machine>=2.16.0
 honcho>=2
 openapi-core>=0.18.2
 openapi-pydantic>=0.4.0
-pytest>=8.3
+pytest>=8.1
 pytest-cov>=4.0.0
 pytest-django>=4.9.0
 pytest-fail-slow>=0.3.0