Remove srcs_version and python_version attributes, as they already default to "PY3"

PiperOrigin-RevId: 720941515

Author: oprypin

tensorflow_probability/python/experimental/linalg/BUILD

@@ -123,7 +123,6 @@ multi_substrate_py_library(
 multi_substrate_py_test(
     name = "linear_operator_row_block_test",
     srcs = ["linear_operator_row_block_test.py"],
-    python_version = "PY3",
     deps = [
         ":linear_operator_row_block",
         # numpy dep,

tensorflow_probability/python/sts/BUILD

@@ -238,7 +238,6 @@ multi_substrate_py_test(
     name = "regularization_test",
     size = "small",
     srcs = ["regularization_test.py"],
-    srcs_version = "PY2AND3",
     deps = [
         ":regularization",
         # numpy dep,