Pin PyQt6 back on Ubuntu 20.04

QuLogic · QuLogic · commit a99ffa9f557e · 2024-07-19T18:50:34.000-04:00
The 6.7.1 wheels on PyPI do not confirm to manylinux 2.28 due to
requiring glibc 2.35 symbols, and cannot be loaded on Ubuntu 20.04,
which has glibc 2.31. So we need to pin that back to avoid the failures.
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
@@ -69,7 +69,7 @@ jobs:
             CFLAGS: "-fno-lto"  # Ensure that disabling LTO works.
             # https://github.com/matplotlib/matplotlib/pull/26052#issuecomment-1574595954
             # https://www.riverbankcomputing.com/pipermail/pyqt/2023-November/045606.html
-            pyqt6-ver: '!=6.5.1,!=6.6.0'
+            pyqt6-ver: '!=6.5.1,!=6.6.0,!=6.7.1'
             # https://bugreports.qt.io/projects/PYSIDE/issues/PYSIDE-2346
             pyside6-ver: '!=6.5.1'
           - os: ubuntu-22.04
