net/http: build error chains in transport that can be unwrapped
In some places of the HTTP transport errors were constructed that
wrapped other errors without providing the ability to call
`errors.Unwrap` on them to get the underlying error.
These places have been fixed to use `%w` when using `fmt.Errorf`
or to implement `Unwrap() error`.
Fixes #56435
Change-Id: Ieed3359281574485c8d0b18298e25e5f1e14555c
GitHub-Last-Rev:
504efbc507a50bd2cf63001511733e232927089f
GitHub-Pull-Request: golang/go#56451
Reviewed-on: https://go-review.googlesource.com/c/go/+/445775
Reviewed-by: Damien Neil <dneil@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Auto-Submit: Damien Neil <dneil@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Damien Neil <dneil@google.com>