Swap apache-client with apache5-client

This commit swaps the default apache-client dependency of service
modules with apache5-client. Applications just relying on the default
HTTP client will now use `Apache5HttpClient` as a result.

Author: dagnir

.changes/next-release/feature-AWSSDKforJavav2-890d71f.json

@@ -0,0 +1,6 @@
+{
+    "type": "feature",
+    "category": "AWS SDK for Java v2",
+    "contributor": "",
+    "description": "This update replaces the default `apache-client` runtime dependency of service clients with the new `apache5-client`. This means that service clients will now use the `Apache5HttClient` by default if no HTTP client is explicitly configured on the service client builder. The SDK version is also updates to `2.42.0` to reflect this change in default client."
+}

services/pom.xml

@@ -522,7 +522,7 @@
             <version>${awsjavasdk.version}</version>
         </dependency>
         <dependency>
-            <artifactId>apache-client</artifactId>
+            <artifactId>apache5-client</artifactId>
             <groupId>software.amazon.awssdk</groupId>
             <version>${awsjavasdk.version}</version>
             <scope>runtime</scope>