chore(bazel): update protobuf to v3.21.7 (#231)

- [ ] Regenerate this pull request now. PiperOrigin-RevId: 477955264 Source-Link: https://togithub.com/googleapis/googleapis/commit/a724450af76d0001f23602684c49cd6a4b3a5654 Source-Link: https://togithub.com/googleapis/googleapis-gen/commit/4abcbcaec855e74a0b22a4988cf9e0eb61a83094 Copy-Tag: eyJwIjoiLmdpdGh1Yi8uT3dsQm90LnlhbWwiLCJoIjoiNGFiY2JjYWVjODU1ZTc0YTBiMjJhNDk4OGNmOWUwZWI2MWE4MzA5NCJ9

Author: gcf-owl-bot[bot]

README.md

@@ -22,20 +22,20 @@ If you are using Maven, add this to your pom.xml file:
 <dependency>
  <groupId>com.google.cloud</groupId>
  <artifactId>google-cloud-network-security</artifactId>
- <version>0.6.2</version>
+ <version>0.6.3</version>
 </dependency>
 ```
 
 If you are using Gradle without BOM, add this to your dependencies:
 
 ```Groovy
-implementation 'com.google.cloud:google-cloud-network-security:0.6.2'
+implementation 'com.google.cloud:google-cloud-network-security:0.6.3'
 ```
 
 If you are using SBT, add this to your dependencies:
 
 ```Scala
-libraryDependencies += "com.google.cloud" % "google-cloud-network-security" % "0.6.2"
+libraryDependencies += "com.google.cloud" % "google-cloud-network-security" % "0.6.3"
 ```
 
 ## Authentication