build: rename _toc to toc (#94)

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Source-Link: googleapis/synthtool@99c93fe

Author: yoshi-automation

handwritten/bigquery-storage/.kokoro/release/docs-devsite.sh

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/nodejs-bigquery-storage.git",
-        "sha": "02eff9cbb2c9961bd528ba19b27c1406cdae0713"
+        "sha": "4b083b1431952cc0b62dd9bbebdbccc3832cc244"
       }
     },
     {
@@ -19,7 +19,7 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "21f1470ecd01424dc91c70f1a7c798e4e87d1eec"
+        "sha": "99c93fe09f8c1dca09dfc0301c8668e3a70dd796"
       }
     }
   ],