Prefer startsWith over indexOf === 0

Faster and make code clearer

src/common/InputHandler.ts

@@ -1780,7 +1780,7 @@ export class InputHandler extends Disposable implements IInputHandler {
    * @param term The terminal name to evaluate
    */
   private _is(term: string): boolean {
-    return (this._optionsService.rawOptions.termName + '').indexOf(term) === 0;
+    return (this._optionsService.rawOptions.termName + '').startsWith(term);
   }
 
   /**

src/common/input/XParseColor.ts

@@ -24,7 +24,7 @@ export function parseColor(data: string): [number, number, number] | undefined {
   if (!data) return;
   // also handle uppercases
   let low = data.toLowerCase();
-  if (low.indexOf('rgb:') === 0) {
+  if (low.startsWith('rgb:')) {
     // 'rgb:' specifier
     low = low.slice(4);
     const m = RGB_REX.exec(low);
@@ -36,7 +36,7 @@ export function parseColor(data: string): [number, number, number] | undefined {
         Math.round(parseInt(m[3] || m[6] || m[9] || m[12], 16) / base * 255)
       ];
     }
-  } else if (low.indexOf('#') === 0) {
+  } else if (low.startsWith('#')) {
     // '#' specifier
     low = low.slice(1);
     if (HASH_REX.exec(low) && [3, 6, 9, 12].includes(low.length)) {