[KYUUBI #3930] [Fix] fix ut in SessionSigningSuite by getting session…

… public key and user sign from LocalProperty

### _Why are the changes needed?_

Followed by issue #3930 and pr #3932.

- correct ut in SessionSigningSuite by fetching session public key and user sign via scala scripts instead of `SET` command in SQL , to prevent accidently redacted by `spark.redaction.regex`
- removed `syncronized` in SignUtils introduced in pr #3932 , with confirming no thread safe problem during the signing and verification

### _How was this patch tested?_
- [x] Add some test cases that check the changes thoroughly including negative and positive cases if possible

- [ ] Add screenshots for manual tests if appropriate

- [x] [Run test](https://kyuubi.apache.org/docs/latest/develop_tools/testing.html#running-tests) locally before make a pull request

Closes #3974 from bowenliang123/3932-fix2.

Closes #3930

c5f07b9 [liangbowen] comment
1f4ace3 [liangbowen] use KyuubiReservedKeys.KYUUBI_SESSION_USER_SIGN/KYUUBI_SESSION_SIGN_PUBLICKEY for property name
a034cbe [liangbowen] style
1f127c1 [liangbowen] remove `synchronized` from `signWithPrivateKey` and `verifySignWithECDSA` in SignUtils
ff5a21d [liangbowen] fix ut by getting `kyuubi.session.sign.publickey` and `kyuubi.session.user.sign` via `spark.sparkContext.getLocalProperty` in scala scripts.

Authored-by: liangbowen <liangbowen@gf.com.cn>
Signed-off-by: ulysses-you <ulyssesyou@apache.org>

kyuubi-common/src/main/scala/org/apache/kyuubi/util/SignUtils.scala

@@ -46,7 +46,7 @@ object SignUtils {
   def signWithPrivateKey(
       plainText: String,
       privateKey: PrivateKey,
-      algorithm: String = "SHA256withECDSA"): String = synchronized {
+      algorithm: String = "SHA256withECDSA"): String = {
     val privateSignature = Signature.getInstance(algorithm)
     privateSignature.initSign(privateKey)
     privateSignature.update(plainText.getBytes(StandardCharsets.UTF_8))
@@ -57,7 +57,7 @@ object SignUtils {
   def verifySignWithECDSA(
       plainText: String,
       signatureBase64: String,
-      publicKeyBase64: String): Boolean = synchronized {
+      publicKeyBase64: String): Boolean = {
     try {
       val publicKeyBytes = Base64.getDecoder.decode(publicKeyBase64)
       val publicKey: PublicKey = KeyFactory.getInstance(KEYPAIR_ALGORITHM_EC)

kyuubi-server/src/test/scala/org/apache/kyuubi/session/SessionSigningSuite.scala

@@ -17,6 +17,8 @@
 
 package org.apache.kyuubi.session
 
+import org.apache.commons.lang3.StringUtils
+
 import org.apache.kyuubi.WithKyuubiServer
 import org.apache.kyuubi.config.KyuubiConf
 import org.apache.kyuubi.config.KyuubiConf._
@@ -68,19 +70,29 @@ class SessionSigningSuite extends WithKyuubiServer with HiveJDBCTestHelper {
   test("KYUUBI #3839 session user sign - check session user sign") {
     withSessionConf()()() {
       withJdbcStatement() { statement =>
-        val rs1 = statement.executeQuery(s"SET $KYUUBI_SESSION_SIGN_PUBLICKEY")
+        val value = s"SET ${OPERATION_LANGUAGE.key}=scala"
+        statement.executeQuery(value)
+
+        val rs1 = statement.executeQuery(
+          s"""
+             |spark.sparkContext.getLocalProperty("$KYUUBI_SESSION_SIGN_PUBLICKEY")
+             |""".stripMargin)
         assert(rs1.next())
-        assert(rs1.getString("value").nonEmpty)
 
-        val rs2 = statement.executeQuery(s"SET $KYUUBI_SESSION_USER_SIGN")
+        val rs2 = statement.executeQuery(
+          s"""
+             |spark.sparkContext.getLocalProperty("$KYUUBI_SESSION_USER_SIGN")
+             |""".stripMargin)
         assert(rs2.next())
-        assert(rs2.getString("value").nonEmpty)
 
-        val publicKeyStr = rs1.getString("value")
-        val sessionUserSign = rs2.getString("value")
+        // skipping prefix "res0: String = " of returned scala result
+        val publicKeyStr = rs1.getString(1).substring(15)
+        val sessionUserSign = rs2.getString(1).substring(15)
+
+        assert(StringUtils.isNotBlank(publicKeyStr))
+        assert(StringUtils.isNotBlank(sessionUserSign))
         assert(SignUtils.verifySignWithECDSA(user, sessionUserSign, publicKeyStr))
       }
     }
   }
-
 }