`BlazeServerBuilder` uses deprecated version of `apply`

[alexandervanhecke]

Hi, I just instantiated the https g8 using the following parameters :

• scala 2.13.2
• sbt 1.3.10
• http4s 0.21.4
• circe 0.13.0

(default values for other parameters)

this does not compile out of the box for me because the BlazeServerBuilder uses the apply method without parameters. That version is deprecated, which results in a compile error.

This is easily fixed by using the apply method that takes an ExecutionContext as a parameter, ie

BlazeServerBuilder[F](ExecutionContext.global)

Let me know if you want me to provide a PR.

[ChristopherDavenport]

PR super appreciated.