[maven-release-plugin] prepare for next development iteration

Author: ascopes

pom.xml

@@ -21,7 +21,7 @@
 
   <groupId>io.github.ascopes</groupId>
   <artifactId>protobuf-maven-plugin-parent</artifactId>
-  <version>4.0.0-M3</version>
+  <version>4.0.0-M4-SNAPSHOT</version>
 
   <name>Protobuf Maven Plugin Parent</name>
   <description>Parent POM for the Protobuf Maven Plugin.</description>
@@ -83,7 +83,7 @@
     <url>https://github.com/ascopes/protobuf-maven-plugin</url>
     <connection>scm:git:https://github.com/ascopes/protobuf-maven-plugin</connection>
     <developerConnection>scm:git:https://github.com/ascopes/protobuf-maven-plugin</developerConnection>
-    <tag>v4.0.0-M3</tag>
+    <tag>HEAD</tag>
   </scm>
 
   <properties>

protobuf-maven-plugin/pom.xml

@@ -22,7 +22,7 @@
   <parent>
     <groupId>io.github.ascopes</groupId>
     <artifactId>protobuf-maven-plugin-parent</artifactId>
-    <version>4.0.0-M3</version>
+    <version>4.0.0-M4-SNAPSHOT</version>
   </parent>
 
   <artifactId>protobuf-maven-plugin</artifactId>