Add RubyGems artifact upload route

Closes #345

See merge request gitlab-org/gitlab-workhorse!680

Add upload route for RubyGems accelerated
uploads.

Cleanup Connection headers

See merge request gitlab-org/gitlab-workhorse!678

[ci skip]

Revert "Merge branch 'jv-git-http-routing' into 'master'"

See merge request gitlab-org/gitlab-workhorse!681

This reverts merge request !670

Remove "/-/" and "incoming/" sections from the debian upload route NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!679

[ci skip]

See https://gitlab.com/gitlab-org/gitlab-workhorse/-/issues/343

Accept more paths as Git HTTP

Closes gitlab#294007

See merge request gitlab-org/gitlab-workhorse!670

With the introduction of group wikis we also need to support repository
paths on the toplevel.

We can also make the matching for info refs requests a bit stricter,
by checking for valid `service` parameters in the query string.

Allow blank S3 regions to be used

See merge request gitlab-org/gitlab-workhorse!677

Update GoCloud to v0.21.1+

See merge request gitlab-org/gitlab-workhorse!675

This dependency update is the first step to supporting Azure Managed
Identities (https://gitlab.com/gitlab-org/gitlab/-/issues/242245) so
that static credentials are not needed. This is equivalent to Amazon's
IAM instance profile.

This GoCloud update also requires a newer gprc-go version. v1.34.1
fixes a UNIX socket dialing issue that was broken in v1.34.0:
https://github.com/grpc/grpc-go/issues/3990

Part of https://gitlab.com/gitlab-org/gitlab/-/issues/242245

If consolidated object storage is used without a region, Workhorse will
fall back to making a direct HTTP PUT call to the S3 endpoint because
GitLab Rails does not send the multipart upload URLs in this mode.

However, this will result a 411 Length Required error because multipart
upload URLs must be used when the Content-Length header is not
available.

An S3 region is not strictly required, particularly with Minio. With
Amazon S3, the region will default to US East (`us-east-1`). If the
bucket does not exist in the region, S3 will return with a more
informative error.

Relates to https://gitlab.com/gitlab-org/gitlab/-/issues/297227

[ci skip]

Add missing testcase for DELETE NO CHANGELOG

Closes #342

See merge request gitlab-org/gitlab-workhorse!676

PNG decoder proxy that skips iCCP chunks

Closes #341

See merge request gitlab-org/gitlab-workhorse!673

This is pretty terrible but I wanted to see how it might work.

Reject unknown HTTP methods

See merge request gitlab-org/security/gitlab-workhorse!17

Run CI against Go 1.15 NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!674

too long method name results in too long
prometheus label name, which can crash prometheus

Makefile: remove find NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!669

Refactor logging helpers to reduce signature creep

See merge request gitlab-org/gitlab-workhorse!662

Document scripts/update-workhorse for releasing NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!668

[ci skip]

Add notice about canonical source NO CHANGELOG

See merge request gitlab-org/gitlab-workhorse!667

Support alternate document root directory

See merge request gitlab-org/gitlab-workhorse!626