Disable protocol upgrades for the HTTP client by default.

[jtorin]

Summary

This avoids problems where a connection could be blocked by an intermediate proxy that disallows protocol upgrades.

Issue

In OTP PR #6079 the Apache HTTP client was upgraded 5.4. They in turn enabled protocol upgrades by default in HTTPCLIENT-751. This means that the client/server will try upgrading a plain HTTP connection to a TLS one (among other upgrades).

Unfortunately this causes problems in our deployment as we run an Envoy proxy server on top of our instances (specifically our SIRI updaters can't connect to the history service). Envoy currently doesn't support protocol upgrades by default and will answer the request with 403.

For the curious, Envoy have issues open on the subject: Envoy #36305, Envoy #36469

There is also a slightly heated Apache HTTP client bug ticket HTTPCLIENT-2344 - which is closed as 'invalid', and which indicates that the current behavior wont change.

This subject was discussed and agreed in a dev meeting that it's better to disable protocol upgrades by default for all clients.
If wanted, it could be enabled on an individual case by adding a configuration API on the OTP HTTP client.

Testing

Tested in a runtime environment.

[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 69.90%. Comparing base (cee960f) to head (2e0a034).
Report is 25 commits behind head on dev-2.x.

Files with missing lines	Patch %	Lines
...rg/opentripplanner/framework/io/OtpHttpClient.java	0.00%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             dev-2.x    #6194      +/-   ##
=============================================
- Coverage      69.90%   69.90%   -0.01%     
+ Complexity     17723    17720       -3     
=============================================
  Files           1998     1998              
  Lines          75443    75445       +2     
  Branches        7718     7718              
=============================================
- Hits           52740    52739       -1     
- Misses         20025    20026       +1     
- Partials        2678     2680       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.