BlazePackageSearchScope: Override correct method for hashcode impleme…

…ntation

SearchScope.hashcode() is marked as being non-extendable. According to the
Javadoc description, calcHashCode() should instead be overridden to provide
a custom hashcode implementation whose result can be cache. Caching seems
to be necessary for performance reasons especially for Kotlin projects
(see commit message of the change in the IntelliJ platform:
JetBrains/intellij-community@ecc334d).

This issue was flagged by the IntelliJ Plugin Verifier.

PiperOrigin-RevId: 357726823

base/src/com/google/idea/blaze/base/lang/buildfile/search/BlazePackageSearchScope.java

@@ -81,7 +81,7 @@ public boolean equals(Object obj) {
   }
 
   @Override
-  public int hashCode() {
+  public int calcHashCode() {
     return Objects.hash(blazePackage, onlyBlazeFiles);
   }