Fix publish to pypi action (#1127)

In #1124, I accidentally added a line doing a `pip install .` package
install to the publish flow.

This is silly, we shouldn't need to be installing the package before
building the package for pypi, and it appears to be causing failures
on the action:
https://github.com/keras-team/keras-nlp/actions/runs/5513665846/jobs/10052068366

These were not caught because we don't run the pypi action on each PR.

.github/workflows/publish-to-pypi.yml

@@ -10,7 +10,6 @@ jobs:
     - name: Install dependencies
       run: |
           pip install -r requirements.txt --progress-bar off
-          pip install --no-deps -e "." --progress-bar off
     - name: Build a binary wheel and a source tarball
       run: >-
         python pip_build.py