docs: bump stale README dependency snippet versions to 0.12

Author: dfa1

README.md

@@ -107,7 +107,7 @@ choices; the build runs on any supported OS/arch.
 <dependency>
   <groupId>io.github.dfa1.zstd</groupId>
   <artifactId>zstd-platform</artifactId>
-  <version>0.11</version>
+  <version>0.12</version>
 </dependency>
 ```
 
@@ -120,7 +120,7 @@ plus only the `zstd-native-<classifier>` you target.
     <dependency>
       <groupId>io.github.dfa1.zstd</groupId>
       <artifactId>zstd-bom</artifactId>
-      <version>0.11</version>
+      <version>0.12</version>
       <type>pom</type>
       <scope>import</scope>
     </dependency>