Support multi-validator in script context accept test.

examples/acceptance_tests/script_context/v3/validators/mint.ak

@@ -0,0 +1,18 @@
+use aiken/dict
+use aiken/transaction.{
+  InlineDatum, Input, Output, OutputReference, ScriptContext, Spend, Spending,
+}
+use aiken/transaction/credential.{Address, ScriptCredential}
+use aiken/transaction/value
+
+validator {
+  fn mint_1(_tmp2: Void, ctx: ScriptContext) {
+    True
+  }
+}
+
+validator {
+  fn mint_2(_tmp2: Void, ctx: ScriptContext) {
+    True
+  }
+}