8325444: GHA: JDK-8325194 causes a regression

Reviewed-by: gdams, shade, ihse

.github/actions/get-jtreg/action.yml

@@ -56,8 +56,14 @@ runs:
 
     - name: 'Build JTReg'
       run: |
+        # If runner architecture is x64 set JAVA_HOME_17_X64 otherwise set to JAVA_HOME_17_arm64
+        if [[ '${{ runner.arch }}' == 'X64' ]]; then
+          JDK="$JAVA_HOME_17_X64"
+        else
+          JDK="$JAVA_HOME_17_arm64"
+        fi
         # Build JTReg and move files to the proper locations
-        bash make/build.sh --jdk "$(realpath bootjdk/jdk)"
+        bash make/build.sh --jdk "$JDK"
         mkdir ../installed
         mv build/images/jtreg/* ../installed
       working-directory: jtreg/src