deps: update dependency com.google.cloud:google-cloud-pubsublite-parent to v1.8.0 (#464)

Author: renovate-bot

pom.xml

@@ -3,7 +3,7 @@
  <parent>
  <groupId>com.google.cloud</groupId>
  <artifactId>google-cloud-pubsublite-parent</artifactId>
- <version>1.6.3</version>
+ <version>1.8.0</version>
  </parent>
  <modelVersion>4.0.0</modelVersion>
  <artifactId>pubsublite-spark-sql-streaming</artifactId>