chore: update templates (#6)

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Source-Link: googleapis/synthtool@778d8be
Source-Link: googleapis/synthtool@573f765

.github/header-checker-lint.yml

@@ -0,0 +1,15 @@
+{"allowedCopyrightHolders": ["Google LLC"],
+ "allowedLicenses": ["Apache-2.0", "MIT", "BSD-3"],
+ "ignoreFiles": ["**/requirements.txt", "**/requirements-test.txt"],
+ "sourceFileExtensions": [
+ 	"ts", 
+ 	"js", 
+ 	"java", 
+ 	"sh", 
+ 	"Dockerfile", 
+ 	"yaml", 
+ 	"py",
+ 	"html",
+ 	"txt"
+ ]
+}

noxfile.py

@@ -86,6 +86,7 @@ def default(session):
     session.install(
         "mock", "pytest", "pytest-cov",
     )
+
     session.install("-e", ".")
 
     # Run py.test against the unit tests.

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/python-channel.git",
-        "sha": "fae81e441e9a31e505e94a640f6aee9dbe42ea81"
+        "sha": "6d0a2da2130c68fb4091fd1245ada5adabbce132"
       }
     },
     {
@@ -19,14 +19,14 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "ba960d730416fe05c50547e975ce79fcee52c671"
+        "sha": "778d8beae28d6d87eb01fdc839a4b4d966ed2ebe"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "ba960d730416fe05c50547e975ce79fcee52c671"
+        "sha": "778d8beae28d6d87eb01fdc839a4b4d966ed2ebe"
       }
     }
   ],
@@ -49,6 +49,7 @@
     ".github/ISSUE_TEMPLATE/feature_request.md",
     ".github/ISSUE_TEMPLATE/support_request.md",
     ".github/PULL_REQUEST_TEMPLATE.md",
+    ".github/header-checker-lint.yml",
     ".github/release-please.yml",
     ".github/snippet-bot.yml",
     ".gitignore",