cibuild.sh: drop pip --force-reinstall for now

according to https://github.com/apache/nuttx/pull/7903
it was to fix "the macOS runners occasionally failing".

cython issue workaround seems more important because it always fails.

tools/ci/cibuild.sh

@@ -290,9 +290,7 @@ function python-tools {
   pip3 install --pre dist/PyYAML-5.4.1.tar.gz
   cd ..
 
-  # Force the reinstall of python packages due to issues with GitHub
-  # cache restoration.
-  pip3 install --force-reinstall \
+  pip3 install \
     cmake-format \
     CodeChecker \
     cvt2utf \