Remove unnecessary else

I think that `else` is unnecessary because it throws in the previous `if`.

Author: abetomo

lib/pip.js

@@ -59,9 +59,8 @@ function installRequirements() {
     if (res.error.code === 'ENOENT') {
       if (this.options.dockerizePip) {
         throw new Error('docker not found! Please install it.');
-      } else {
-        throw new Error(`${this.options.pythonBin} not found! Try the pythonBin option.`);
       }
+      throw new Error(`${this.options.pythonBin} not found! Try the pythonBin option.`);
     }
     throw new Error(res.error);
   }