docker in docker fix

Author: sukovanej

lib/pip.js

@@ -86,8 +86,13 @@ function installRequirements(
     }
     serverless.cli.log(`Docker Image: ${dockerImage}`);
 
-    // Prepare bind path depending on os platform
-    const bindPath = getBindPath(servicePath);
+    let bindPath;
+    if (options.dockerInDocker) {
+      bindPath = process.env['host_pwd'];
+    } else {
+      // Prepare bind path depending on os platform
+      bindPath = getBindPath(servicePath);
+    }
 
     cmdOptions = ['run', '--rm', '-v', `"${bindPath}:/var/task:z"`];
     if (options.dockerSsh) {