chore: remove duplicate dependency declarations

[chingor13]

Warning:  
Warning:  Some problems were encountered while building the effective model for com.google.cloud:google-cloud-compute:jar:1.97.0-SNAPSHOT
Warning:  'dependencies.dependency.(groupId:artifactId:type:classifier)' must be unique: com.google.api:gax-grpc:jar -> duplicate declaration of version (?) @ line 95, column 17
Warning:  
Warning:  Some problems were encountered while building the effective model for com.google.cloud:google-cloud-recommender:jar:2.89.0-SNAPSHOT
Warning:  'dependencies.dependency.(groupId:artifactId:type:classifier)' must be unique: com.google.api:gax:jar:testlib -> duplicate declaration of version (?) @ line 108, column 17
Warning:  
Warning:  Some problems were encountered while building the effective model for com.google.cloud:google-cloud-speech:jar:4.82.0-SNAPSHOT
Warning:  'dependencies.dependency.(groupId:artifactId:type:classifier)' must be unique: com.google.api:gax:jar:testlib -> duplicate declaration of version (?) @ line 110, column 17