Move contracts wasm test code into separate files (#5337)

* Move contracts wasm test code into separate files

* Move crypto_hashes into a separate file

* Load wasm code at runtime

* Move wasm files

* Fix wasm formatting

* Update crypto_hashes file

substrate/frame/contracts/tests/dispatch_call.wat

@@ -0,0 +1,14 @@
+(module
+	(import "env" "ext_dispatch_call" (func $ext_dispatch_call (param i32 i32)))
+	(import "env" "memory" (memory 1 1))
+
+	(func (export "call")
+		(call $ext_dispatch_call
+			(i32.const 8) ;; Pointer to the start of encoded call buffer
+			(i32.const 11) ;; Length of the buffer
+		)
+	)
+	(func (export "deploy"))
+
+	(data (i32.const 8) "\00\00\03\00\00\00\00\00\00\00\C8")
+)