fix: run tests sequentially to avoid race conditions with shared state

Author: diegosantdev

.gitignore

@@ -7,6 +7,7 @@ node_modules/
 # LicensePulse data
 .licensepulse/
 watchlist.json
+test-integration-watchlist.json
 
 # Test coverage
 coverage/

jest.config.js

@@ -15,5 +15,6 @@ module.exports = {
       lines: 45,
       statements: 45
     }
-  }
+  },
+  maxWorkers: 1
 };