Move insecure randomness query to cwe-338

Also give it a precision

ql/src/Security/CWE-338/InsecureRandomness.ql

@@ -3,9 +3,10 @@
  * @description Using insufficient randomness as the key of a cryptographic algorithm can allow an attacker to compromise security.
  * @kind path-problem
  * @problem.severity error
+ * @precision high
  * @id go/insecure-randomness
  * @tags security
- *      external/cwe/cwe-327
+ *       external/cwe/cwe-338
  */
 
 import go

ql/test/query-tests/Security/CWE-327/Crypto.go

@@ -9,7 +9,7 @@ import (
 	"crypto/sha256"
 )
 
-func main() {
+func crypto() {
 	public := []byte("hello")
 
 	password := []byte("123456")

ql/test/query-tests/Security/CWE-327/InsecureRandomness/InsecureRandomness.qlref

@@ -1 +0,0 @@
-Security/CWE-327/InsecureRandomness.ql

ql/test/query-tests/Security/CWE-338/InsecureRandomness/InsecureRandomness.qlref

@@ -0,0 +1 @@
+Security/CWE-338/InsecureRandomness.ql