docs: add intersphinx to proto-plus library (#86)

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Source-Link: googleapis/synthtool@ea52b8a
Source-Link: googleapis/synthtool@fd3584b

docs/conf.py

@@ -349,6 +349,7 @@
     "google-auth": ("https://google-auth.readthedocs.io/en/stable", None),
     "google.api_core": ("https://googleapis.dev/python/google-api-core/latest/", None,),
     "grpc": ("https://grpc.io/grpc/python/", None),
+    "proto-plus": ("https://proto-plus-python.readthedocs.io/en/latest/", None),
 }
 
 

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/python-bigquery-storage.git",
-        "sha": "8115f88db7c355c96f7cff235406e744e7b08c67"
+        "sha": "20ed21d40cd4f89c3d4ae5d8db7ed3c6b801cc4c"
       }
     },
     {
@@ -19,14 +19,14 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5f6ef0ec5501d33c4667885b37a7685a30d41a76"
+        "sha": "ea52b8a0bd560f72f376efcf45197fb7c8869120"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "5f6ef0ec5501d33c4667885b37a7685a30d41a76"
+        "sha": "ea52b8a0bd560f72f376efcf45197fb7c8869120"
       }
     }
   ],