[pom] Use ${revision} replace specific version.

[joyCurry30]

As we use specific version like "3.0-SNAPSHOT", we need to repeat modifications between different modules. So why not use a placeholder like ${revision}.

[whhe]

If 'revision' property is used, we should also add the flatten-maven-plugin, refer to https://maven.apache.org/maven-ci-friendly.html#install-deploy

[joyCurry30]

@whhe I add the flatten-maven-plugin. cc plz.

[whhe]

LGTM, wait for ci to pass.

[leonardBang]

Thanks @joyCurry30 and @whhe for the contribution and review, I've one minor question: What's the meaning revision? could we use maven default properties ${project.version} in this case ?

[whhe]

Thanks @joyCurry30 and @whhe for the contribution and review, I've one minor question: What's the meaning revision? could we use maven default properties ${project.version} in this case ?

As we need to declare ${project.version} explicitly in each pom file (the parent part), we need a new property to set a original value for it, and revision is a common option to be used here.

[leonardBang]

Thanks @whhe for the explanation, got it.