Fix developerConnection warning

> [INFO] --- maven-hpi-plugin:3.38:validate (default-validate) @ nomad ---
> [WARNING] <developerConnection>scm:git:ssh://git@github.com/jenkinsci/${project.artifactId}-plugin.git</developerConnection> is invalid because ssh:// URLs do not work well with PCT.
>   Replace it with <developerConnection>scm:git:git@github.com:jenkinsci/${project.artifactId}-plugin.git</developerConnection>.
>   In the future this warning will be changed to an error and will break the build.

pom.xml

@@ -26,9 +26,8 @@
     </licenses>
 
     <scm>
-        <connection>scm:git:ssh://github.com/jenkinsci/nomad-plugin.git</connection>
-        <developerConnection>scm:git:ssh://git@github.com/jenkinsci/nomad-plugin.git
-        </developerConnection>
+        <connection>scm:git:git@github.com:jenkinsci/nomad-plugin.git</connection>
+        <developerConnection>scm:git:git@github.com:jenkinsci/${project.artifactId}-plugin.git</developerConnection>
         <url>https://github.com/jenkinsci/nomad-plugin</url>
         <tag>${scmTag}</tag>
     </scm>