Add support for finer grained censoring of user defined warnings

[kl0tl]

This pull request adds a --censor-user-defined-warnings=WARNING flag to ignore Warn constraints whose message contains WARNING. It can be specified multiple times to ignore different warnings.

For instance, given this spago.dhall:

{ name = "censor-user-defined-warnings"
, dependencies = [ "effect", "prelude" ]
, packages = https://raw.githubusercontent.com/purescript/package-sets/prepare-0.14/src/packages.dhall
, sources = [ "src/**/*.purs" ]
}

the following program:

-- src/Example.purs
module Example where

import Prelude

import Effect (Effect)
import Prim.TypeError (class Warn, Text)

foo :: Warn (Text "'foo' is deprecated") => Unit
foo = unit

bar :: Warn (Text "'bar' is deprecated") => Unit
bar = unit

main :: Effect Unit
main = pure foo *> pure bar

yields those warnings when compiled with npx spago build:

[1/2 UserDefinedWarning] src/Example.purs:14:1

  14  main :: Effect Unit
      ^^^^^^^^^^^^^^^^^^^
  
  A custom warning occurred while solving type class constraints:
  
    'foo' is deprecated
  
  in value declaration main

[2/2 UserDefinedWarning] src/Example.purs:14:1

  14  main :: Effect Unit
      ^^^^^^^^^^^^^^^^^^^
  
  A custom warning occurred while solving type class constraints:
  
    'bar' is deprecated
  
  in value declaration main

Compiling with npx spago build -u "--censor-user-defined-warnings=\"'foo' is deprecated\"" yields:

[1/1 UserDefinedWarning] src/Example.purs:14:1

  14  main :: Effect Unit
      ^^^^^^^^^^^^^^^^^^^
  
  A custom warning occurred while solving type class constraints:
  
    'bar' is deprecated
  
  in value declaration main

Compiling with npx spago build -u "--strict --censor-user-defined-warnings=\"'foo' is deprecated\" --censor-user-defined-warnings=\"bar\"" yields no warnings.

This doesn’t alter the behaviour of the existing --censor-warnings and --censor-codes=UserDefinedWarning flags: psa --censor-warnings --censor-user-defined-warnings=WARNING still censor all warnings and psa --censor-codes=UserDefinedWarning --censor-user-defined-warnings=WARNING still censor all user defined warnings.

purescript-psa-utils has been updated with the latest Argonaut libraries, which introduces typed errors, on master so I also had to make three small unrelated changes.

[kl0tl]

I’ll point back to a version number once natefaubion/purescript-psa-utils#10 is merged and a new version is released.