End support for python 3.9 (#1728)

* remove python 3.9 from workflow

* remove 3.9 from docs and ask questions about if requirements can be updated

* remove comments

---------

Co-authored-by: Sufi Kaur <sufikaur@lbl.gov>

Author: sufikaur

.github/workflows/core.yml

@@ -90,7 +90,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13']
+        python-version: ['3.10', '3.11', '3.12', '3.13']
         os:
           - linux
           - win64

.github/workflows/integration.yml

@@ -126,7 +126,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13']
+        python-version: ['3.10', '3.11', '3.12', '3.13']
         os:
           - linux
           - win64
@@ -164,7 +164,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.9', '3.10', '3.11', '3.12', '3.13']
+        python-version: ['3.10', '3.11', '3.12', '3.13']
         os:
           - linux
           - win64

README.md

@@ -82,7 +82,6 @@ Most of the functionality is implemented in Python. In accordance with
 the end-of-life for many Python 2 libraries, the IDAES Toolkit is written
 for Python 3. The following sub-versions are supported:
 
-* Python 3.9
 * Python 3.10
 * Python 3.11
 * Python 3.12

pyproject.toml

@@ -25,7 +25,6 @@ classifiers=[
     "Operating System :: Unix",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",