[SPARK-15745][SQL] Use classloader's getResource() for reading resource files in HiveTests

## What changes were proposed in this pull request?

This is a cleaner approach in general but my motivation behind this change in particular is to be able to run these tests from anywhere without relying on system properties.

## How was this patch tested?

Test only change

Author: Sameer Agarwal <sameer@databricks.com>

Closes #13489 from sameeragarwal/resourcepath.

sql/hive/src/main/scala/org/apache/spark/sql/hive/test/TestHive.scala

@@ -179,19 +179,8 @@ private[hive] class TestHiveSparkSession(
   hiveFilesTemp.mkdir()
   ShutdownHookManager.registerShutdownDeleteDir(hiveFilesTemp)
 
-  val inRepoTests = if (System.getProperty("user.dir").endsWith("sql" + File.separator + "hive")) {
-    new File("src" + File.separator + "test" + File.separator + "resources" + File.separator)
-  } else {
-    new File("sql" + File.separator + "hive" + File.separator + "src" + File.separator + "test" +
-      File.separator + "resources")
-  }
-
   def getHiveFile(path: String): File = {
-    val stripped = path.replaceAll("""\.\.\/""", "").replace('/', File.separatorChar)
-    hiveDevHome
-      .map(new File(_, stripped))
-      .filter(_.exists)
-      .getOrElse(new File(inRepoTests, stripped))
+    new File(Thread.currentThread().getContextClassLoader.getResource(path).getFile)
   }
 
   val describedTable = "DESCRIBE (\\w+)".r