fix(starters): update gatsby monorepo

Author: renovate-bot

starters/blog/package-lock.json

@@ -8,14 +8,14 @@
     "url": "https://github.com/gatsbyjs/gatsby/issues"
   },
   "dependencies": {
-    "gatsby": "^2.1.30",
-    "gatsby-image": "^2.0.32",
+    "gatsby": "^2.1.31",
+    "gatsby-image": "^2.0.33",
     "gatsby-plugin-feed": "^2.0.15",
     "gatsby-plugin-google-analytics": "^2.0.17",
-    "gatsby-plugin-manifest": "^2.0.23",
+    "gatsby-plugin-manifest": "^2.0.24",
     "gatsby-plugin-offline": "^2.0.25",
     "gatsby-plugin-react-helmet": "^3.0.9",
-    "gatsby-plugin-sharp": "^2.0.27",
+    "gatsby-plugin-sharp": "^2.0.28",
     "gatsby-plugin-typography": "^2.2.9",
     "gatsby-remark-copy-linked-files": "^2.0.10",
     "gatsby-remark-images": "^2.0.6",
@@ -24,7 +24,7 @@
     "gatsby-remark-smartypants": "^2.0.9",
     "gatsby-source-filesystem": "^2.0.24",
     "gatsby-transformer-remark": "^2.3.2",
-    "gatsby-transformer-sharp": "^2.1.16",
+    "gatsby-transformer-sharp": "^2.1.17",
     "prismjs": "^1.15.0",
     "react": "^16.8.4",
     "react-dom": "^16.8.4",