chore: fix a few issues from eslint

Author: JairusSW

src/compiler.ts

@@ -1783,7 +1783,6 @@ export class Compiler extends DiagnosticEmitter {
     let module = this.module;
     let bodyNode = assert(instance.prototype.bodyNode);
     let returnType = instance.signature.returnType;
-    let signature = instance.signature;
     let numReturnTypes = instance.signature.numReturnTypes;
     let flow = this.currentFlow;
     let thisLocal = instance.signature.thisType
@@ -6802,7 +6801,6 @@ export class Compiler extends DiagnosticEmitter {
     let sizeTypeRef = usizeType.toRef();
     let parameterTypes = instance.signature.parameterTypes;
     let returnType = instance.signature.returnType;
-    let resultRefs = instance.signature.resultRefs;
     let hasReturnValue = instance.signature.numReturnTypes > 0;
     let numParameters = parameterTypes.length;
     let tempIndex = 1 + parameterTypes.length; // incl. `this`