[pillow] fix build failure after Python 10.x upgrade

Prior to the Python 10 upgrade in the base-runner image there was
no version-less `python` executable; only `python3` was available
so some projects worked around that by symlinking the latter to the
former.

The Python version upgrade also included a change that applied similar
symbolic links of common executable names for convenience. This caused
a conflict for projects applying it again, and broke the build.

Removing the now redundant python3 -> python executable symlink resolves
the failure.

projects/pillow/Dockerfile

@@ -29,8 +29,7 @@ RUN $SRC/Pillow/Tests/oss-fuzz/build_dictionaries.sh
 
 COPY build_depends.sh $SRC
 
-RUN ln -s /usr/local/bin/python3 /usr/local/bin/python \
-    && ln -s /bin/true /usr/local/bin/yum_install \
+RUN ln -s /bin/true /usr/local/bin/yum_install \
     && ln -s /bin/true /usr/local/bin/yum \
     && cd $SRC/Pillow \
     && git submodule update --init wheels/multibuild \