test: add exporter-metrics in upper-bound check

[suztomo]

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Fixes #<issue_number_goes_here> ☕️

[suztomo]

shared-dependencies version check / Shared Dependencies BOM upper-bound check (pull_request) failed:

Error:  Failed to execute goal org.apache.maven.plugins:maven-enforcer-plugin:3.5.0:enforce (enforce) on project shared-dependencies-upper-bound-test: 
Error:  Rule 2: org.apache.maven.enforcer.rules.dependency.RequireUpperBoundDeps failed with message:
Error:  Failed while enforcing RequireUpperBoundDeps. The error(s) are [
Error:  Require upper bound dependencies error for org.slf4j:slf4j-api:1.7.36 paths to dependency are:
Error:  +-com.google.cloud:shared-dependencies-upper-bound-test:3.50.1-SNAPSHOT
Error:    +-org.apache.httpcomponents.client5:httpclient5:5.3.1
Error:      +-org.slf4j:slf4j-api:1.7.36
Error:  and
Error:  +-com.google.cloud:shared-dependencies-upper-bound-test:3.50.1-SNAPSHOT
Error:    +-com.google.cloud.opentelemetry:exporter-metrics:0.33.0
Error:      +-org.slf4j:slf4j-api:2.0.16
Error:  ]
Error:  -> [Help 1]

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'java_showcase_integration_tests'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'java_showcase_integration_tests'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'gapic-generator-java-root'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed for 'java_showcase_integration_tests'

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[suztomo]

It still failed even after updating today's main branch:

Error:  Failed to execute goal org.apache.maven.plugins:maven-enforcer-plugin:3.5.0:enforce (enforce) on project shared-dependencies-upper-bound-test: 
Error:  Rule 2: org.apache.maven.enforcer.rules.dependency.RequireUpperBoundDeps failed with message:
Error:  Failed while enforcing RequireUpperBoundDeps. The error(s) are [
Error:  Require upper bound dependencies error for org.slf4j:slf4j-api:1.7.36 paths to dependency are:
Error:  +-com.google.cloud:shared-dependencies-upper-bound-test:3.55.1
Error:    +-org.apache.httpcomponents.client5:httpclient5:5.3.1
Error:      +-org.slf4j:slf4j-api:1.7.36
Error:  and
Error:  +-com.google.cloud:shared-dependencies-upper-bound-test:3.55.1
Error:    +-com.google.cloud.opentelemetry:exporter-metrics:0.33.0
Error:      +-org.slf4j:slf4j-api:2.0.16
Error:  ]
Error:  -> [Help 1]