chore: Add header checker config (#1171)

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Source-Link: googleapis/synthtool@573f765

Author: yoshi-automation

.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"
+ ]
+}

docs/dyn/index.md

@@ -564,6 +564,7 @@
 
 
 ## memcache
+* [v1](http://googleapis.github.io/google-api-python-client/docs/dyn/memcache_v1.html)
 * [v1beta2](http://googleapis.github.io/google-api-python-client/docs/dyn/memcache_v1beta2.html)
 
 
@@ -651,6 +652,7 @@
 
 ## realtimebidding
 * [v1](http://googleapis.github.io/google-api-python-client/docs/dyn/realtimebidding_v1.html)
+* [v1alpha](http://googleapis.github.io/google-api-python-client/docs/dyn/realtimebidding_v1alpha.html)
 
 
 ## recommendationengine

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/google-api-python-client.git",
-        "sha": "cc94ec86e652769e9d3d5cb6d6491efb8d76dd21"
+        "sha": "4576f024c5c021e50e912ea5768213ab293c2593"
       }
     },
     {
@@ -18,7 +18,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "fb53b6fb373b7c3edf4e55f3e8036bc6d73fa483"
+        "sha": "573f7655311b553a937f9123bee17bf78497db95"
       }
     }
   ],
@@ -28,6 +28,7 @@
     ".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",
     ".kokoro/build.sh",