docs(redirects): add redirect for Word Pattern problem

apps/docs/redirects.ts

@@ -60,6 +60,7 @@ export default [
   { from: "/236", to: "/tree-dfs/lowest-common-ancestor-of-a-binary-tree" },
   { from: "/238", to: "/prefix-sum/product-of-array-except-self" },
   { from: "/242", to: "/hash-table/valid-anagram" },
+  { from: "/290", to: "/hash-table/word-pattern" },
   { from: "/303", to: "/prefix-sum/range-sum-query-immutable" },
   { from: "/322", to: "/1d-dynamic-programming/coin-change" },
   { from: "/323", to: "/union-find/number-of-connected-components-in-an-undirected-graph" },