Use ResourceUtils.getURL to resolve the viewsDir location to a `j…

…ava.net.URL`

It will make Grace apps works with Spring Framework 6.1 and Spring Boot 3.2 and 3.3

Closes gh-526

grace-plugin-gsp/src/main/groovy/org/grails/plugins/web/GroovyPagesAutoConfiguration.java

@@ -39,6 +39,7 @@
 import org.springframework.core.io.ResourceLoader;
 import org.springframework.util.ClassUtils;
 import org.springframework.util.CollectionUtils;
+import org.springframework.util.ResourceUtils;
 import org.springframework.util.StringUtils;
 
 import grails.config.Config;
@@ -97,13 +98,13 @@ public GroovyPageResourceLoader groovyPageResourceLoader(ObjectProvider<GrailsAp
         GroovyPageResourceLoader groovyPageResourceLoader = new GroovyPageResourceLoader();
         Resource baseResource;
         if (StringUtils.hasText(viewsDir)) {
-            baseResource = new FileUrlResource(viewsDir);
+            baseResource = new FileUrlResource(ResourceUtils.getURL(viewsDir));
         }
         else if (warDeployedWithReload && env.hasReloadLocation()) {
-            baseResource = new FileUrlResource(transformToValidLocation(env.getReloadLocation()));
+            baseResource = new FileUrlResource(ResourceUtils.getURL(env.getReloadLocation()));
         }
         else {
-            baseResource = new FileUrlResource(transformToValidLocation(BuildSettings.BASE_DIR.getAbsolutePath()));
+            baseResource = new FileUrlResource(ResourceUtils.getURL(BuildSettings.BASE_DIR.getCanonicalPath()));
         }
         groovyPageResourceLoader.setBaseResource(baseResource);
 
@@ -321,14 +322,4 @@ public DefaultGroovyPagesUriService groovyPagesUriService() {
         return new DefaultGroovyPagesUriService();
     }
 
-    private static String transformToValidLocation(String location) {
-        if (location.equals(".")) {
-            return location;
-        }
-        if (!location.endsWith(java.io.File.separator)) {
-            return location + java.io.File.separator;
-        }
-        return location;
-    }
-
 }