[SPARK-32407][SPARK-35375][INFRA][DOCS] Delete comments on Sphinx and Jinja2

### What changes were proposed in this pull request?
Delete comments on `Sphinx` and `Jinja2`

### Why are the changes needed?
they had been upgraded in apache#44012

### Does this PR introduce _any_ user-facing change?
no

### How was this patch tested?
ci

### Was this patch authored or co-authored using generative AI tooling?
no

Closes apache#44046 from zhengruifeng/infra_Sphinx_nit.

Authored-by: Ruifeng Zheng <ruifengz@apache.org>
Signed-off-by: Hyukjin Kwon <gurwls223@apache.org>

Author: zhengruifeng

.github/workflows/build_and_test.yml

@@ -692,10 +692,6 @@ jobs:
     - name: Install Python linter dependencies
       if: inputs.branch != 'branch-3.3' && inputs.branch != 'branch-3.4' && inputs.branch != 'branch-3.5'
       run: |
-        # TODO(SPARK-32407): Sphinx 3.1+ does not correctly index nested classes.
-        #   See also https://github.com/sphinx-doc/sphinx/issues/7551.
-        # Jinja2 3.0.0+ causes error when building with Sphinx.
-        #   See also https://issues.apache.org/jira/browse/SPARK-35375.
         python3.9 -m pip install 'flake8==3.9.0' pydata_sphinx_theme 'mypy==0.982' 'pytest==7.1.3' 'pytest-mypy-plugins==1.9.3' numpydoc 'jinja2<3.0.0' 'black==23.9.1'
         python3.9 -m pip install 'pandas-stubs==1.2.0.53' ipython 'grpcio==1.59.3' 'grpc-stubs==1.24.11' 'googleapis-common-protos-stubs==2.2.0'
     - name: Python linter
@@ -745,10 +741,6 @@ jobs:
         Rscript -e "devtools::install_version('preferably', version='0.4', repos='https://cloud.r-project.org')"
     - name: Install dependencies for documentation generation
       run: |
-        # TODO(SPARK-32407): Sphinx 3.1+ does not correctly index nested classes.
-        #   See also https://github.com/sphinx-doc/sphinx/issues/7551.
-        # Jinja2 3.0.0+ causes error when building with Sphinx.
-        #   See also https://issues.apache.org/jira/browse/SPARK-35375.
         # Pin the MarkupSafe to 2.0.1 to resolve the CI error.
         #   See also https://issues.apache.org/jira/browse/SPARK-38279.
         python3.9 -m pip install 'sphinx==4.2.0' mkdocs 'pydata_sphinx_theme>=0.13' sphinx-copybutton nbsphinx numpydoc jinja2 'markupsafe==2.0.1' 'pyzmq<24.0.0'