[qt-kit] dev-python/PyQt6-sip-13.11.1 requires py3.10

```
running build_ext
building 'PyQt6.sip' extension
creating /var/tmp/portage/dev-python/PyQt6-sip-13.11.1/work/pyqt6_sip-13.11.1-python3_9/temp.linux-x86_64-3.9
x86_64-pc-linux-gnu-gcc -mtune=generic -O2 -pipe -fPIC -I/usr/include/python3.9 -c sip_array.c -o /var/tmp/portage/dev-python/PyQt6-sip-13.11.1/work/pyqt6_sip-13.11.1-python3_9/temp.linux-x86_64-3.9/sip_array.o
In file included from sip_core.h:21,
from sip_array.c:17:
sip.h:18:2: error: #error "This version of PyQt6.sip requires Python v3.10 or later"
18 | #error "This version of PyQt6.sip requires Python v3.10 or later"
| ^~~~~
error: command '/usr/bin/x86_64-pc-linux-gnu-gcc' failed with exit code 1
* ERROR: dev-python/PyQt6-sip-13.11.1::qt-kit failed (compile phase):
* (no error message)
```

Start with the dev-python/PyQt6-sip-13.11.1 package build and reproduce the compile phase using Python 3.9. Read the reported sip.h requirement and the package's build configuration to determine the expected compatibility behavior. Done means the package build no longer fails for the supported Python versions.

Written by the indexing model from the issue text.