pom.xml: change gerrit-war's dependency on gerrit-main to runtime

Previously, the dependency was set to 'provided' (meaning required at
compile time but not to be deployed), but the Main class from
gerrit-main is required at runtime because the shipped manifest in the
.war package references Main in its main-class attribute. Also, it
doesn't appear to use Main outside of the manifest, so it's not
actually required at compile time.

This only seems to matter to IntelliJ, since the Main class is
provided to the war via an overlay in gerrit-war/pom.xml

Change-Id: I80598fed0c5e5b5a6e59de6ae7ca5f3669a22cfa
diff --git a/gerrit-war/pom.xml b/gerrit-war/pom.xml
index 110f966..db58ae2 100644
--- a/gerrit-war/pom.xml
+++ b/gerrit-war/pom.xml
@@ -53,7 +53,7 @@
       <groupId>com.google.gerrit</groupId>
       <artifactId>gerrit-main</artifactId>
       <version>${project.version}</version>
-      <scope>provided</scope>
+      <scope>runtime</scope>
     </dependency>
 
     <dependency>