Fail if unsupported okhttp3 is found.

[balamurugana]

As okhttp 4.x and 3.x use same package name okhttp3, minio-java
fails at middle of runtime if okhttp 3.x is used. This patch fails
at beginning if unsupported okhttp3 is found.

Signed-off-by: Bala.FA bala.gluster@gmail.com

[odin568]

As a consequence using this libary against SpringBoot 2.5.3 (latest) causes (expected) exceptions:
Unsupported OkHttp library found. Must use okhttp >= 4.8.1

Dependency Versions: https://docs.spring.io/spring-boot/docs/current/reference/html/dependency-versions.html#

Upgrade to okhttp4 was rejected till now, don't know for when it is planned.
spring-projects/spring-boot#18506

Not sure if being so strict is a good idea. What is the reasoning behind?

[balamurugana]

As a consequence using this libary against SpringBoot 2.5.3 (latest) causes (expected) exceptions:
Unsupported OkHttp library found. Must use okhttp >= 4.8.1

Dependency Versions: https://docs.spring.io/spring-boot/docs/current/reference/html/dependency-versions.html#

Upgrade to okhttp4 was rejected till now, don't know for when it is planned.
spring-projects/spring-boot#18506

Not sure if being so strict is a good idea. What is the reasoning behind?

As mentioned in the description of this PR, the failure happens if okhttp v3 is used. With this PR, you get an error in prior by custom error.