[CELEBORN-1911] Move multipart-uploader to multipart-uploader/multipart-uploader-s3 for extensibility

### What changes were proposed in this pull request?
- close [CELEBORN-1911](https://issues.apache.org/jira/browse/CELEBORN-1911)

This PR refactors the project structure by moving the multipart-uploader module into multipart-uploader/multipart-uploader-s3.

### Why are the changes needed?
This change improves modularity and enables future extensions, such as multipart-uploader/multipart-uploader-oss, allowing better support for multiple object storage backends.

### Does this PR introduce _any_ user-facing change?
No

### How was this patch tested?
Deployment integration testing has been completed in the local environment.

Closes #3153 from shouwangyw/optimize/mpu-s3.

Authored-by: veli.yang <897900564@qq.com>
Signed-off-by: mingji <fengmingxiao.fmx@alibaba-inc.com>

multipart-uploader/multipart-uploader-s3/pom.xml

@@ -21,12 +21,12 @@
     <groupId>org.apache.celeborn</groupId>
     <artifactId>celeborn-parent_${scala.binary.version}</artifactId>
     <version>${project.version}</version>
-    <relativePath>../pom.xml</relativePath>
+    <relativePath>../../pom.xml</relativePath>
   </parent>
 
-  <artifactId>celeborn-multipart-uploader_${scala.binary.version}</artifactId>
+  <artifactId>celeborn-multipart-uploader-s3_${scala.binary.version}</artifactId>
   <packaging>jar</packaging>
-  <name>Celeborn Multipart Uploader</name>
+  <name>Celeborn Multipart Uploader S3</name>
 
   <dependencies>
     <dependency>

pom.xml

@@ -1345,7 +1345,7 @@
     <profile>
       <id>aws</id>
       <modules>
-        <module>multipart-uploader</module>
+        <module>multipart-uploader/multipart-uploader-s3</module>
       </modules>
       <properties>
         <aws-deps>true</aws-deps>

project/CelebornBuild.scala

@@ -569,7 +569,7 @@ object CeleborMPU {
 
   lazy val hadoopAwsDependencies = Seq(Dependencies.hadoopAws, Dependencies.awsS3)
 
-  lazy val celeborMPU = Project("celeborn-multipart-uploader", file("multipart-uploader"))
+  lazy val celeborMPU = Project("celeborn-multipart-uploader-s3", file("multipart-uploader/multipart-uploader-s3"))
     .dependsOn(CelebornService.service % "test->test;compile->compile")
     .settings (
       commonSettings,

worker/pom.xml

@@ -148,7 +148,7 @@
       <dependencies>
         <dependency>
           <groupId>org.apache.celeborn</groupId>
-          <artifactId>celeborn-multipart-uploader_${scala.binary.version}</artifactId>
+          <artifactId>celeborn-multipart-uploader-s3_${scala.binary.version}</artifactId>
           <version>${project.version}</version>
         </dependency>
       </dependencies>