fix(cli): add timeout for running solutions

cli/services/Docker.ts

@@ -1,9 +1,12 @@
 import execa from 'execa'
 import ora from 'ora'
+import ms from 'ms'
 
-class Docker {
+export class Docker {
   static CONTAINER_TAG = 'programming-challenges'
   static SIGSEGV_EXIT_CODE = 139
+  static MAXIMUM_TIMEOUT = '1 minute'
+  static MAXIMUM_TIMEOUT_MILLISECONDS = ms(Docker.MAXIMUM_TIMEOUT)
 
   public async build (): Promise<void> {
     const loader = ora('Building the Docker image').start()
@@ -23,13 +26,22 @@ class Docker {
         input
       }
     )
+    let isValid = true
+    const timeout = setTimeout(() => {
+      subprocess.kill()
+      isValid = false
+    }, Docker.MAXIMUM_TIMEOUT_MILLISECONDS)
     try {
       const { stdout, stderr } = await subprocess
       if (stderr.length !== 0) {
         throw new Error(stderr)
       }
+      clearTimeout(timeout)
       return stdout
     } catch (error: any) {
+      if (!isValid) {
+        throw new Error(`Timeout: time limit exceeded (${Docker.MAXIMUM_TIMEOUT}), try to optimize your solution.`)
+      }
       if (error.exitCode === Docker.SIGSEGV_EXIT_CODE) {
         throw new Error('Docker run failed: SIGSEGV indicates a segmentation fault (attempts to access a memory location that it\'s not allowed to access).')
       }