Show list of enabled features with rerun --version

[emilk]

• Reverts Revert "Show list of enabled feature with rerun --version" #7770
• Re-applies Show list of enabled feature with rerun --version #7744

The revert was because during cargo publish, a Cargo.lock file materialized, and that made cargo angry:

Failed to publish re_sdk:
error: failed to verify package tarball

Caused by:
  Source directory was modified by build.rs during cargo publish. Build scripts should not modify anything outside of OUT_DIR.
  Added: /home/runner/work/rerun/rerun/target/package/re_sdk-0.19.0-alpha.9/Cargo.lock

So in this PR we only query about which cargo features if we're NOT in a cargo publish build. That should work! We'll know when we next publish some crates :)

[Wumpf]

👍