chore(deps): update dependency grpcio to v1.27.2 (GoogleCloudPlatform#3173)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [grpcio](https://grpc.io) | minor | `==1.25.0` -> `==1.27.2` |
| [grpcio](https://grpc.io) | minor | `==1.23.0` -> `==1.27.2` |
| [grpcio](https://grpc.io) | minor | `==1.26.0` -> `==1.27.2` |
| [grpcio](https://grpc.io) | patch | `==1.27.1` -> `==1.27.2` |

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dataproc/requirements.txt

@@ -1,4 +1,4 @@
-grpcio==1.27.1
+grpcio==1.27.2
 google-auth==1.11.2
 google-auth-httplib2==0.0.3
 google-cloud==0.34.0

endpoints/bookstore-grpc-transcoding/requirements.txt

@@ -1,4 +1,4 @@
-grpcio==1.27.1
+grpcio==1.27.2
 grpcio-tools==1.27.2
 google-auth==1.11.2
 six==1.14.0

endpoints/bookstore-grpc/requirements.txt

@@ -1,4 +1,4 @@
-grpcio==1.27.1
+grpcio==1.27.2
 grpcio-tools==1.27.2
 google-auth==1.11.2
 six==1.14.0

endpoints/getting-started-grpc/requirements.txt

@@ -1,2 +1,2 @@
-grpcio==1.26.0
+grpcio==1.27.2
 grpcio-tools==1.27.2

opencensus/requirements.txt

@@ -1,3 +1,3 @@
-grpcio==1.23.0
+grpcio==1.27.2
 opencensus-ext-stackdriver==0.7.2
 opencensus==0.7.7

trace/cloud-trace-demo-app/app/requirements.txt

@@ -5,5 +5,5 @@ Flask==1.1.1
 opencensus-ext-stackdriver==0.7.2
 opencensus-ext-flask==0.7.3
 opencensus-context==0.1.1
-grpcio==1.25.0
+grpcio==1.27.2
 httpretty==0.9.7