chore: Move some linter rules into the multitab tests directory

Author: jcoglan

.eslintrc.json

@@ -21,8 +21,7 @@
     "ArrayBuffer": "readonly",
     "FileReaderSync": "readonly",
     "emit": "readonly",
-    "PouchDB": "readonly",
-    "__pouch__": "readonly"
+    "PouchDB": "readonly"
   },
 
   "rules": {

tests/multitab/.eslintrc.json

@@ -0,0 +1,7 @@
+{
+  "extends": "../.eslintrc.json",
+
+  "globals": {
+    "__pouch__": "readonly"
+  }
+}