fix: not initialize MetricsReporter if not support prometheus

[qyi71]

What is the purpose of the change

if set config set
dubbo: metrics: enable: false enable-collector-sync: false enable-jvm: false enable-metadata: false enable-metrics-init: false enable-threadpool: false enable-registry: false enable-rpc: false export-metrics-service: false protocol: prometheus port: 9090
and import dubbo-spring-boot-starter of version 3.2.6

it will print wran "java.lang.NoClassDefFoundError: io/prometheus/client/exporter/HttpConnectionFactory"

Brief changelog

Verifying this change

org.apache.dubbo.config.deploy.DefaultApplicationDeployerTest#isImportPrometheus

Checklist

• [] Make sure there is a GitHub_issue field for the change (usually before you start working on it). Trivial changes like typos do not require a GitHub issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue.
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[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
33.3% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud