Revert "Re-compile PyInstaller bootloader in CI."

This reverts commit 6042fccbf5.

tox.ini

@@ -191,7 +191,6 @@ passenv =
     APPDATA
     HOME
     PYINSTALLER_DEBUG
-    PYINSTALLER_COMPILE_BOOTLOADER
 setenv =
     qt5: PYINSTALLER_QT5=true
 deps =
@@ -281,7 +280,6 @@ passenv = *
 # Override default PyQt6 from [testenv]
 setenv =
     qt5: QUTE_QT_WRAPPER=PyQt5
-    PYINSTALLER_COMPILE_BOOTLOADER=true
 usedevelop = true
 deps =
     -r{toxinidir}/requirements.txt