docs: Update dependency management version

Author: tzolov

mcp-docs/src/main/antora/modules/ROOT/pages/dependency-management.adoc

@@ -22,7 +22,7 @@ Maven::
         <dependency>
             <groupId>org.springframework.experimental</groupId>
             <artifactId>mcp-bom</artifactId>
-            <version>0.5.0</version>
+            <version>0.6.0-SNAPSHOT</version>
             <type>pom</type>
             <scope>import</scope>
         </dependency>
@@ -35,7 +35,7 @@ Gradle::
 [source,groovy,indent=0,subs="verbatim,quotes"]
 ----
 dependencies {
-  implementation platform("org.springframework.experimental:mcp-bom:0.5.0")
+  implementation platform("org.springframework.experimental:mcp-bom:0.6.0-SNAPSHOT")
   //...
 }
 ----