refact: clean up unused variables & setup matching lint rule

package.json

@@ -21,7 +21,7 @@
     "develop": "gatsby develop",
     "fetch-users": "node ./scripts/fetchUsers.js",
     "format": "prettier --write src/**/*.{js,jsx}",
-    "lint": "tslint -c tslint.json '{src,scripts}/**/*.{js,ts,tsx}'",
+    "lint": "tslint -p tsconfig.json -c tslint.json '{src,scripts}/**/*.{js,ts,tsx}'",
     "lint:fix": "npm run lint -- --fix",
     "serve": "gatsby serve",
     "start": "npm run develop",

src/components/Footer/styles.tsx

@@ -1,4 +1,3 @@
-import { Link } from "gatsby"
 import styled from "styled-components"
 
 export const FooterWrapper = styled.footer`

src/components/Layout/index.tsx

@@ -5,7 +5,6 @@
  * See: https://www.gatsbyjs.org/docs/use-static-query/
  */
 
-import { graphql, useStaticQuery } from "gatsby"
 import React, { Fragment, PropsWithChildren } from "react"
 
 import { GlobalStyles } from "../../globalStyles"
@@ -20,15 +19,6 @@ export function Layout({
   location,
 }: PropsWithChildren<{ location: Location }>) {
   const isHome = location.pathname === "/"
-  const data = useStaticQuery(graphql`
-    query {
-      site {
-        siteMetadata {
-          title
-        }
-      }
-    }
-  `)
 
   return (
     <SC.LayoutWrapper>

src/pages/about.tsx

@@ -1,6 +1,6 @@
 import { graphql } from "gatsby"
 import React, { Fragment } from "react"
-import { MarkdownRemark, Query } from "../../generated/graphql"
+import { MarkdownRemark } from "../../generated/graphql"
 import { Markdown } from "../components/Markdown"
 import { SEO } from "../components/SEO"
 

src/pages/index.tsx

@@ -1,4 +1,3 @@
-import { Link } from "gatsby"
 import React, { Fragment } from "react"
 
 import { SEO } from "../components/SEO"

src/pages/rules.tsx

@@ -1,6 +1,6 @@
 import { graphql } from "gatsby"
 import React, { Fragment } from "react"
-import { MarkdownRemark, Query } from "../../generated/graphql"
+import { MarkdownRemark } from "../../generated/graphql"
 import { Markdown } from "../components/Markdown"
 import { SEO } from "../components/SEO"
 

tslint.json

@@ -27,6 +27,7 @@
     "no-eval": true,
     "no-parameter-reassignment": true,
     "no-submodule-imports": false,
+    "no-unused-variable": true,
 
     "react-hooks-nesting": "error"
   },