[fix][misc] Class conflict during jetcd-core-shaded shading process

[Shawyeok]

Motivation

In the latest release candidates (3.0.8-candidate-1, 4.0.1-candidate-1), the jetcd-core-shaded module shading issue persists. This occurs because the maven-shade-plugin includes the current project artifact in the shade process. In jetcd-core-shaded, we copy io.etcd.jetcd.* into the jetcd-core-shaded jar without relocation. As a result, when the install or deploy goals are executed without cleaning the target folder, class conflicts arise between io.etcd.jetcd.* inside org.apache.pulsar:jetcd-core-shaded.jar and io.etcd:jetcd-core.jar.

#23604 attempted to resolve this issue but failed to account for build and deploy in separate steps during the release process.

Verifying this Change

To verify this patch, follow these steps:

# Step 1: Clean and install the `jetcd-core-shaded` module.
mvn clean install -pl jetcd-core-shaded -DskipTests

# Step 2: Install without cleaning, simulating a release process.
mvn install -pl jetcd-core-shaded -DskipTests

# Step 3: Unpack the shaded jar into a directory and verify imports.
# Ensure that the import statement for `io.netty.handler.logging.ByteBufFormat` 
# in `org/apache/pulsar/jetcd/shaded/io/vertx/core/net/NetClientOptions.class` 
# is correct. The expected import is:
# `import io.grpc.netty.shaded.io.netty.handler.logging.ByteBufFormat;`.
unzip $M2_REPO/org/apache/pulsar/jetcd-core-shaded/<VERSION>/jetcd-core-shaded-<VERSION>-shaded.jar \
  -d jetcd-core-shaded/target/shaded-classes

Does this pull request potentially affect one of the following parts:

If the box was checked, please highlight the changes

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment

Documentation

• doc
• doc-required
• doc-not-needed
• doc-complete

Matching PR in forked repository

PR in forked repository: Shawyeok#20

[lhotari]

LGTM. Good work @Shawyeok. Thanks for finding the root cause and addressing the problem.

[lhotari]

@Shawyeok Please submit a similar PR to BookKeeper for jetcd-core-shaded.

[Shawyeok]

@Shawyeok Please submit a similar PR to BookKeeper for jetcd-core-shaded.

@lhotari
apache/bookkeeper#4532 please feel free to take a look, thanks.