Add benchmark test case .wasm with lots of unique fn types

[Robbepop]

Crafted an example module for this comment: #1701 (comment)
Note: we already had a module with lots of types, but they were all empty function types, so I crafted another module with all unique function types.
The test case has the following form and contains over 5000 unique function types.

cc @alexcrichton

(module
	(type (func (param i32) ))
	(type (func (param i64) ))
	(type (func (param f32) ))
	(type (func (param f64) ))
	(type (func (param i32) (param i32) ))
	(type (func (param i32) (param i64) ))
	(type (func (param i32) (param f32) ))
	(type (func (param i32) (param f64) ))
	(type (func (param i64) (param i32) ))
	(type (func (param i64) (param i64) ))
	(type (func (param i64) (param f32) ))
	(type (func (param i64) (param f64) ))
	(type (func (param f32) (param i32) ))
	(type (func (param f32) (param i64) ))
	(type (func (param f32) (param f32) ))
	(type (func (param f32) (param f64) ))
	(type (func (param f64) (param i32) ))
	(type (func (param f64) (param i64) ))
	(type (func (param f64) (param f32) ))
	(type (func (param f64) (param f64) ))
	(type (func (param i32) (param i32) (param i32) ))
	(type (func (param i32) (param i32) (param i64) ))
	(type (func (param i32) (param i32) (param f32) ))
	(type (func (param i32) (param i32) (param f64) ))
	;; etc..
	(type (func (param f64) (param f64) (param f64) (param f64) (result f32) (result i32) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f32) (result i64) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f32) (result f32) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f32) (result f64) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f64) (result i32) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f64) (result i64) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f64) (result f32) ))
	(type (func (param f64) (param f64) (param f64) (param f64) (result f64) (result f64) ))
)

Running both validation benchmark test cases for lot-of-types: