build: Replace gen-opa-wasm.sh with generic go runner

There is nothing wasm-specific about the script and it will need to be
reused for feature generation.

Signed-off-by: Torin Sandall <torinsandall@gmail.com>

build/gen-opa-wasm.sh

@@ -1,5 +0,0 @@
-#!/bin/sh
-
-set -e
-
-GOFLAGS=-mod=vendor GO111MODULE=on GOOS="" GOARCH="" go run $@

build/gen-run-go.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+set -e
+
+GOFLAGS=-mod=vendor GO111MODULE=on GOOS="" GOARCH="" go run $@

main.go

@@ -19,4 +19,4 @@ func main() {
 }
 
 // WASM base binary generation:
-//go:generate build/gen-opa-wasm.sh internal/cmd/genopawasm/main.go -o internal/compiler/wasm/opa/opa.go internal/compiler/wasm/opa/opa.wasm
+//go:generate build/gen-run-go.sh internal/cmd/genopawasm/main.go -o internal/compiler/wasm/opa/opa.go internal/compiler/wasm/opa/opa.wasm