Fix cabal build tools warning

[kvkenyon]

(base) ➜  src git:(main) ✗ stack run -- ../test/csrc/declarators.c -d
Cabal file warning in /Users/kevin/dev/hcc/hcc.cabal@107:3: The field "build-tools" is deprecated in the Cabal specification version 2.0. Please use 'build-tool-depends' field
Cabal file warning in /Users/kevin/dev/hcc/hcc.cabal@76:3: The field "build-tools" is deprecated in the Cabal specification version 2.0. Please use 'build-tool-depends' field
Cabal file warning in /Users/kevin/dev/hcc/hcc.cabal@47:3: The field "build-tools" is deprecated in the Cabal specification version 2.0. Please use 'build-tool-depends' field
var * func * array * static const char
var array * int
y  const int
z array  double
bptr array array * * int
p * array  int
f1 func w/ params  int
var func w/ params * long``