SCALA-400 Rename test classes

This is to follow the unit test naming convention
for classes.

Author: Matteo Di Pirro

zio-2/src/test/scala/com/baeldung/scala/zio/json/DecodingSpec.scala renamed to zio-2/src/test/scala/com/baeldung/scala/zio/json/DecodingTest.scala

@@ -4,7 +4,7 @@ import org.scalatest.matchers.should.Matchers
 import org.scalatest.wordspec.AnyWordSpec
 import zio.json.*
 
-class DecodingSpec extends AnyWordSpec with Matchers {
+class DecodingTest extends AnyWordSpec with Matchers {
   "zio-json" should {
     "decode a JSON object to a case class" in {
       """{"timeout":789}""".fromJson[Start] shouldBe Right(Start(789))

zio-2/src/test/scala/com/baeldung/scala/zio/json/EncodingSpec.scala renamed to zio-2/src/test/scala/com/baeldung/scala/zio/json/EncodingTest.scala

@@ -4,7 +4,7 @@ import org.scalatest.matchers.should.Matchers
 import org.scalatest.wordspec.AnyWordSpec
 import zio.json.*
 
-class EncodingSpec extends AnyWordSpec with Matchers {
+class EncodingTest extends AnyWordSpec with Matchers {
   "zio-json" should {
     "encode a case class to JSON" in {
       Start(100).toJson shouldBe """{"timeout":100}"""