feat: add max items to env variable names (#363)

This adds a new const into `ENV_VARS`. It will be used by worker to pass
the `maxItems` limit from run options to the actor env vars.

Author: novotnyj

packages/consts/src/consts.ts

@@ -375,6 +375,7 @@ export const ENV_VARS = {
     ACTOR_TASK_ID: 'APIFY_ACTOR_TASK_ID',
     ACTOR_BUILD_ID: 'APIFY_ACTOR_BUILD_ID',
     ACTOR_BUILD_NUMBER: 'APIFY_ACTOR_BUILD_NUMBER',
+    ACTOR_MAX_ITEMS: 'APIFY_ACTOR_MAX_ITEMS',
     INPUT_KEY: 'APIFY_INPUT_KEY',
     USER_ID: 'APIFY_USER_ID',
     TOKEN: 'APIFY_TOKEN',