jest: add page (#2528)

pages/common/jest.md

@@ -0,0 +1,23 @@
+# jest
+
+> A zero-configuration JavaScript testing platform.
+
+- Run all tests:
+
+`jest`
+
+- Run only tests with a name that matches the regex pattern:
+
+`jest -t {{spec_name}}`
+
+- Run only tests relating to uncommitted files:
+
+`jest --onlyChanged`
+
+- Watch files for changes and rerun related tests:
+
+`jest --watch`
+
+- Show help:
+
+`jest --help`