improved support for subtyping in applicativeError syntax

[mberndt123]

This is a case that I missed in my last pull request.
new Exception("foo").raiseError[Either[Throwable, ?], Nothing] now compiles; without this patch, you need to write (new Exception("foo"): Throwable).raiseError[Either[Throwable, ?], Nothing]

@LukaJCB , @kailuowang since you merged my last PR, you might want to take a look at this too.

[codecov-io]

Codecov Report

Merging #2518 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2518   +/-   ##
=======================================
  Coverage   95.35%   95.35%           
=======================================
  Files         358      358           
  Lines        6530     6530           
  Branches      282      282           
=======================================
  Hits         6227     6227           
  Misses        303      303

Impacted Files	Coverage Δ
.../src/main/scala/cats/syntax/applicativeError.scala	100% <ø> (ø)	⬆️

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[kailuowang]

This change was already introduced by #2511 which is merged 9 hours ago. It's already in master.

So I am totally confused why I am seeing this diff (meaning the change is not on master) in this PR.
WTH?

[mberndt123]

I based my PR on an older master, I guess that must be why.