Update tensorflow test configurations

tox.ini

@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py{38,39,310,311}, setup, numpy-{120,121,123,200}, tensorflow-{26,27,28,29,210,211}
+envlist = py{38,39,310,311}, setup, numpy-{120,121,123,200}, tensorflow-{212,216}
 
 [testenv]
 deps =
@@ -61,68 +61,26 @@ deps =
 commands =
     pytest tests/test_config {posargs}
 
-[testenv:tensorflow-115]
+[testenv:tensorflow-212]
 basepython = python
 deps =
     -rdev-requirements.txt
-    tensorflow~=1.15.0
+    numpy<2.0.0
+    tensorflow~=2.12.0
 commands =
     pytest tests/test_stflow tests/test_optional.py \
         {posargs}
 
-[testenv:tensorflow-26]
-basepython = python
-deps =
-    -rdev-requirements.txt
-    tensorflow~=2.6.0
-commands =
-    pytest tests/test_stflow tests/test_optional.py \
-        {posargs}
 
-[testenv:tensorflow-27]
+[testenv:tensorflow-216]
 basepython = python
 deps =
     -rdev-requirements.txt
-    tensorflow~=2.7.0
+    tensorflow~=2.16.0
 commands =
     pytest tests/test_stflow tests/test_optional.py \
         {posargs}
 
-[testenv:tensorflow-28]
-basepython = python
-deps =
-    -rdev-requirements.txt
-    tensorflow~=2.8.0
-commands =
-    pytest tests/test_stflow tests/test_optional.py \
-        {posargs}
-
-[testenv:tensorflow-29]
-basepython = python
-deps =
-    -rdev-requirements.txt
-    tensorflow~=2.9.0
-commands =
-    pytest tests/test_stflow tests/test_optional.py \
-        {posargs}
-
-[testenv:tensorflow-210]
-basepython = python
-deps =
-    -rdev-requirements.txt
-    tensorflow~=2.10.0
-commands =
-    pytest tests/test_stflow tests/test_optional.py \
-        {posargs}
-
-[testenv:tensorflow-211]
-basepython = python
-deps =
-    -rdev-requirements.txt
-    tensorflow~=2.11.0
-commands =
-    pytest tests/test_stflow tests/test_optional.py \
-        {posargs}
 
 [testenv:setup]
 basepython = python