[#5] Add MethodOverloadTests for each module

[DevDengChao]

I tested these three test cases. They works fine, but if any fails, try clean and run again.
(Maybe we should migrate to JUnit5 and annount with @RepeatTest)

My environment:

IntelliJ IDEA 2020.3.1
Build #IU-203.6682.168, built on December 29, 2020
Runtime version: 11.0.9.1+11-b1145.63 amd64
VM: OpenJDK 64-Bit Server VM by JetBrains s.r.o.
Windows 10 10.0

ref:
#5

ps:
There is something wrong with jOOR-java-6 and jOOR-java-8's existing test cases.

[lukaseder]

Thanks for your suggestion. We'll consider it, should we decide to implement #5.