Fix pygobject installation for armhf (#20215)

Pycairo 1.27.0 was recently released, which requires cmake for the
build. Pygobject depends on this, and the default of isolated builds
means that any already-installed version of pycairo isn't used.

Fix this by explicitly installing pycairo 1.26.0 and disabling build
isolation.

Signed-off-by: Saikrishna Arcot <sarcot@microsoft.com>

files/build_templates/sonic_debian_extension.j2

@@ -244,7 +244,8 @@ sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install system
 # Install SONiC host services package
 SONIC_HOST_SERVICES_PY3_WHEEL_NAME=$(basename {{sonic_host_services_py3_wheel_path}})
 sudo cp {{sonic_host_services_py3_wheel_path}} $FILESYSTEM_ROOT/$SONIC_HOST_SERVICES_PY3_WHEEL_NAME
-sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install pygobject
+sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install pycairo==1.26.0
+sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install --no-build-isolation pygobject
 sudo https_proxy=$https_proxy LANG=C chroot $FILESYSTEM_ROOT pip3 install $SONIC_HOST_SERVICES_PY3_WHEEL_NAME
 sudo rm -rf $FILESYSTEM_ROOT/$SONIC_HOST_SERVICES_PY3_WHEEL_NAME