Upgrading OkHTTP to 5.0.0

[Ujjwal Kumar Maharana]

What kind of issue is this?

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  https://square.github.io/okhttp/changelogs/changelog/
  OkHTTP 5.0 is on its way. And currently the latest retrofit is dependent on retrofit 3.14.9
  
  When can we expect updating the dependency
  

[Jake Wharton]

OkHttp 5.x is not stable and therefore can't be used.

OkHttp 4.x is written in Kotlin and we're not ready to inflict the Kotlin stdlib dependency on our consumers at this time.

The general plan is:

• Release 2.10 and other 2.x's with the changes on master.
• Release 3.0 as binary and behavioral compatible with 2.x but rewritten in Kotlin with OkHttp 4.x (or 5.x) as a dependency.
• Release 4.0 with breaking changes (following our breaking policy) as Kotlin multiplatform and depending on OkHttp 5.x's multiplatform abstraction.

Retrofit 2.10 will be released within a month or so. There is no timeline for anything else at this time.