chore: update plugin version to 1.2.3

[vpa1977]

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[Copilot]

Pull request overview

This PR updates the rockcraft plugin version from 1.2.2 to 1.2.3 across all POM files, Gradle build scripts, and documentation.

Key Changes:

• Updated parent POM version to 1.2.3
• Updated plugin references in example projects to use version 1.2.3
• Updated documentation to reflect the new version number

Reviewed changes

Copilot reviewed 14 out of 15 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
pom.xml	Updated parent POM version to 1.2.3
rockcraft/pom.xml	Updated parent reference to version 1.2.3
rockcraft-maven/pom.xml	Updated parent reference to version 1.2.3
examples/maven/spring-boot-native/pom.xml	Updated plugin version to 1.2.3
examples/maven/spring-boot-app/pom.xml	Updated plugin version to 1.2.3
examples/maven/shaded-jar/pom.xml	Updated plugin version to 1.2.3
examples/maven/custom-rockcraft/pom.xml	Updated plugin version to 1.2.3
examples/gradle/spring-app/build.gradle	Updated plugin version to 1.2.3
examples/gradle/spring-app-native/build.gradle	Updated plugin version to 1.2.3
examples/gradle/beryx-runtime/build.gradle	Updated plugin version to 1.2.3
examples/gradle/beryx-jlink/build.gradle	Updated plugin version to 1.2.3
examples/gradle/app-options/build.gradle	Updated plugin version to 1.2.3
examples/devcontainer/build.gradle	Updated plugin version to 1.2.3
README.md	Updated documentation examples to reference version 1.2.3

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