Ecosystem CI tests failing because of platform dependencies in integration tests

[holly-cummins]

Some of the integration tests depend on quarkus platform, rather than just quarkus. This is annoying when trying to run locally against a snapshot build, and it's also causing failures in the ecosystem CI (see, for example, https://github.com/quarkiverse/quarkus-pact/actions/runs/4160309746/jobs/7197179102):

2023-02-13T06:30:22.5397530Z [INFO] Running io.quarkiverse.pact.it.TestModeContractTestIT
2023-02-13T06:30:24.3382043Z [INFO] Scanning for projects...
2023-02-13T06:30:24.4858900Z [WARNING] The POM for io.quarkus.platform:quarkus-maven-plugin:jar:2.16.999-SNAPSHOT is missing, no dependency information available
2023-02-13T06:30:24.5232321Z [ERROR] [ERROR] Some problems were encountered while processing the POMs:
2023-02-13T06:30:24.5234310Z [ERROR] Unresolveable build extension: Plugin io.quarkus.platform:quarkus-maven-plugin:2.16.999-SNAPSHOT or one of its dependencies could not be resolved: io.quarkus.platform:quarkus-maven-plugin:jar:2.16.999-SNAPSHOT was not found in https://oss.sonatype.org/content/repositories/snapshots during a previous attempt. This failure was cached in the local repository and resolution is not reattempted until the update interval of snapshots-repo has elapsed or updates are forced @ 
2023-02-13T06:30:24.5236172Z [ERROR] Non-resolvable import POM: io.quarkus.platform:quarkus-bom:pom:2.16.999-SNAPSHOT was not found in https://oss.sonatype.org/content/repositories/snapshots during a previous attempt. This failure was cached in the local repository and resolution is not reattempted until the update interval of snapshots-repo has elapsed or updates are forced @ line 21, column 19