Constraint http2 <4.2

Author: maksbotan

cabal.project

@@ -53,6 +53,12 @@ tests: True
 optimization: False
 -- reorder-goals: True
 
+-- Older warp versions fail to build with https >= 4.2:
+-- Network/Wai/Handler/Warp/HTTP2.hs:48:16: error:
+-- Error:     • Constructor ‘H2.Config’ does not have the required strict field(s): confMySockAddr,
+--                                                                          confPeerSockAddr
+constraints: http2 <4.2
+
 -- wreq-0.5.4.1 doesn't seem to work with ghc-8.6.5
 if (impl(ghc < 8.8))
   constraints: wreq == 0.5.4.0