update asinit to use strictEqual since equal is deprecated

Author: rpivo

NOTICE

@@ -38,6 +38,7 @@ under the licensing terms detailed in LICENSE:
 * yjhmelody <yjh465402634@gmail.com>
 * bnbarak <bn.barak@gmail.com>
 * Colin Eberhardt <colin.eberhardt@gmail.com>
+* Ryan Pivovar <ryanpivovar@gmail.com>
 
 Portions of this software are derived from third-party works licensed under
 the following terms:

bin/asinit

@@ -408,7 +408,7 @@ function ensureTestsIndexJs() {
     fs.writeFileSync(testsIndexFile, [
       "const assert = require(\"assert\");",
       "const myModule = require(\"..\");",
-      "assert.equal(myModule.add(1, 2), 3);",
+      "assert.strictEqual(myModule.add(1, 2), 3);",
       "console.log(\"ok\");"
     ].join("\n") + "\n");
     console.log(colors.green("  Created: ") + testsIndexFile);