Revert deprecation of [Simple]CommandLinePropertySource

This commit reverts the deprecation of CommandLinePropertySource and
SimpleCommandLinePropertySource, since we have discovered that Spring
Boot actively uses SimpleCommandLinePropertySource in
org.springframework.boot.SpringApplication.

Closes gh-31207

Author: sbrannen

spring-context/src/test/kotlin/org/springframework/context/support/BeanDefinitionDslTests.kt

@@ -76,7 +76,6 @@ class BeanDefinitionDslTests {
 	}
 
 	@Test
-	@Suppress("DEPRECATION")
 	fun `Declare beans using environment condition with the functional Kotlin DSL`() {
 		val beans = beans {
 			bean<Foo>()

spring-core/src/main/java/org/springframework/core/env/CommandLinePropertySource.java

@@ -204,9 +204,7 @@
  * @see PropertySource
  * @see SimpleCommandLinePropertySource
  * @see JOptCommandLinePropertySource
- * @deprecated since 6.1 with no plans for a replacement
  */
-@Deprecated(since = "6.1")
 public abstract class CommandLinePropertySource<T> extends EnumerablePropertySource<T> {
 
 	/** The default name given to {@link CommandLinePropertySource} instances: {@value}. */

spring-core/src/main/java/org/springframework/core/env/SimpleCommandLinePropertySource.java

@@ -83,9 +83,7 @@
  * @since 3.1
  * @see CommandLinePropertySource
  * @see JOptCommandLinePropertySource
- * @deprecated since 6.1 with no plans for a replacement
  */
-@Deprecated(since = "6.1")
 public class SimpleCommandLinePropertySource extends CommandLinePropertySource<CommandLineArgs> {
 
 	/**

spring-core/src/test/java/org/springframework/core/env/SimpleCommandLinePropertySourceTests.java

@@ -29,7 +29,6 @@
  * @author Sam Brannen
  * @since 3.1
  */
-@SuppressWarnings("deprecation")
 class SimpleCommandLinePropertySourceTests {
 
 	@Test