chore: drop mention of Python 2.7 from templates (#207)

Source-Link: googleapis/synthtool@facee4c
Post-Processor: gcr.io/repo-automation-bots/owlbot-python:latest@sha256:9743664022bd63a8084be67f144898314c7ca12f0a03e422ac17c733c129d803

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

securitycenter/snippets/noxfile.py

@@ -39,7 +39,7 @@
 
 TEST_CONFIG = {
     # You can opt out from the test for specific Python versions.
-    'ignored_versions': ["2.7"],
+    'ignored_versions': [],
 
     # Old samples are opted out of enforcing Python type hints
     # All new samples should feature them
@@ -88,8 +88,8 @@ def get_pytest_env_vars() -> Dict[str, str]:
 
 
 # DO NOT EDIT - automatically generated.
-# All versions used to tested samples.
-ALL_VERSIONS = ["2.7", "3.6", "3.7", "3.8", "3.9"]
+# All versions used to test samples.
+ALL_VERSIONS = ["3.6", "3.7", "3.8", "3.9"]
 
 # Any default versions that should be ignored.
 IGNORED_VERSIONS = TEST_CONFIG['ignored_versions']