Update package.json

package.json

@@ -17,14 +17,14 @@
         "autoprefixer": "^9.4.7",
         "classnames": "^2.2.6",
         "codemirror": "^5.43.0",
-        "gatsby": "^2.1.4",
+        "gatsby": "^2.21.1",
         "gatsby-image": "^2.0.29",
-        "gatsby-plugin-manifest": "^2.0.17",
+        "gatsby-plugin-manifest": "^2.2.0",
         "gatsby-plugin-offline": "^2.0.23",
         "gatsby-plugin-react-helmet": "^3.0.6",
         "gatsby-plugin-react-svg": "^2.1.1",
         "gatsby-plugin-sass": "^2.0.10",
-        "gatsby-plugin-sharp": "^2.0.29",
+        "gatsby-plugin-sharp": "^2.1.9",
         "gatsby-plugin-sitemap": "^2.0.5",
         "gatsby-remark-copy-linked-files": "^2.0.9",
         "gatsby-remark-images": "^3.0.4",
@@ -33,13 +33,13 @@
         "gatsby-remark-unwrap-images": "^1.0.1",
         "gatsby-source-filesystem": "^2.0.20",
         "gatsby-transformer-remark": "^2.2.5",
-        "gatsby-transformer-sharp": "^2.1.17",
+        "gatsby-transformer-sharp": "^2.1.21",
         "juniper-js": "^0.1.0",
-        "node-sass": "^4.11.0",
+        "node-sass": "^4.12.0",
         "prismjs": "^1.15.0",
         "react": "^16.8.2",
         "react-dom": "^16.8.2",
-        "react-helmet": "^5.2.0",
+        "react-helmet": "^5.2.1",
         "rehype-react": "^3.1.0",
         "remark-react": "^5.0.1",
         "reveal.js": "^3.8.0"