[#8300] fix(cli): fix output message in RemoveModelVersionProperty

[arjnklc]

What changes were proposed in this pull request?

Fixed the output message in RemoveModelVersionProperty.java:

• Added a missing space before "property" in the output string for both alias and version paths.
• Removed the redundant duplicate "property" word from the message, as also flagged by Copilot in PR #9557.

Before: model alias aliasAproperty key property removed.
After: model alias aliasA property key removed.

Why are the changes needed?

The CLI output message in RemoveModelVersionProperty had two issues:

1. A missing space before "property" made the output unreadable (e.g., aliasAproperty).
2. The word "property" appeared twice in the message, making it redundant. This was also identified in the Copilot review of PR #9557.

Fix: #8300

Does this PR introduce any user-facing change?

Yes. The CLI output message when removing a model version property is now correctly formatted and more concise.

How was this patch tested?

No automated tests were added as this is a minor formatting fix. Ran existing CLI tests to verify no regressions:

./gradlew :clients:cli:test --tests "org.apache.gravitino.cli.TestModelCommands"

All tests related to RemoveModelVersionProperty pass.