chore: fix mypy (googleapis#15535)

Fixes googleapis#15533

Author: parthea

.librarian/generator-input/client-post-processing/integrate-isolated-handwritten-code.yaml

@@ -305,3 +305,16 @@ replacements:
               "pandas-stubs",
           )
     count: 1
+  - paths: [
+      packages/google-cloud-bigquery-storage/noxfile.py,
+    ]
+    before: |
+      "types-protobuf",
+      \    \)
+      \    session.install\("."\)
+    after: |
+      "types-protobuf",
+              "pandas-stubs",
+          )
+          session.install(".[fastavro]")
+    count: 1

packages/google-cloud-bigquery-storage/noxfile.py

@@ -112,8 +112,9 @@ def mypy(session):
         "mypy<1.16.0",
         "types-requests",
         "types-protobuf",
+        "pandas-stubs",
     )
-    session.install(".")
+    session.install(".[fastavro]")
     session.run(
         "mypy",
         "-p",