Drop support for Python 3.8

TensorFlow has [dropped support for python 3.8](tensorflow/tensorflow@9a1f8bb).

This updates our CI to use Python 3.9

Author: arcra

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
       fail-fast: false
       matrix:
         tf_version_id: ['tf', 'notf']
-        python_version: ['3.8']
+        python_version: ['3.9']
     steps:
       - uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # v4.3.0
@@ -149,7 +149,7 @@ jobs:
       - uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # v4.3.0
         with:
-          python-version: '3.8'
+          python-version: '3.9'
           architecture: 'x64'
       - name: 'Cache Cargo artifacts'
         if: matrix.mode == 'native'
@@ -217,7 +217,7 @@ jobs:
         # flake8 should run on each Python version that we target,
         # because the errors and warnings can differ due to language
         # changes, and we want to catch them all.
-        python_version: ['3.8', '3.9', '3.10', '3.11']
+        python_version: ['3.9', '3.10', '3.11']
     steps:
       - uses: actions/checkout@ac593985615ec2ede58e132d2e21d2b1cbd6127c # v3.3.0
       - uses: actions/setup-python@13ae5bb136fac2878aff31522b9efb785519f984 # v4.3.0

tensorboard/pip_package/setup.py

@@ -64,7 +64,7 @@ def get_readme():
     },
     install_requires=REQUIRED_PACKAGES,
     tests_require=REQUIRED_PACKAGES,
-    python_requires=">=3.8",
+    python_requires=">=3.9",
     # PyPI package information.
     classifiers=[
         "Development Status :: 4 - Beta",
@@ -73,7 +73,6 @@ def get_readme():
         "Intended Audience :: Science/Research",
         "License :: OSI Approved :: Apache Software License",
         "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.8",
         "Programming Language :: Python :: 3.9",
         "Programming Language :: Python :: 3.10",
         "Programming Language :: Python :: 3.11",