fix: upgrade multiple dependencies with Snyk

Snyk has created this PR to upgrade:
  - gatsby-remark-copy-linked-files from 6.13.1 to 6.13.2.
    See this package in npm: https://www.npmjs.com/package/gatsby-remark-copy-linked-files
  - gatsby-remark-images from 7.13.1 to 7.13.2.
    See this package in npm: https://www.npmjs.com/package/gatsby-remark-images
  - gatsby-remark-prismjs from 7.13.1 to 7.13.2.
    See this package in npm: https://www.npmjs.com/package/gatsby-remark-prismjs
  - gatsby-remark-responsive-iframe from 6.13.1 to 6.13.2.
    See this package in npm: https://www.npmjs.com/package/gatsby-remark-responsive-iframe

See this project in Snyk:
https://app.snyk.io/org/mastermindzh/project/6eb54845-2bb5-45e0-80e2-6b3a1c53eee6?utm_source=github&utm_medium=referral&page=upgrade-pr

package.json

@@ -69,12 +69,12 @@
     "gatsby-plugin-sharp": "^5.13.1",
     "gatsby-plugin-sitemap": "^6.13.1",
     "gatsby-remark-autolink-headers": "^6.13.1",
-    "gatsby-remark-copy-linked-files": "^6.13.1",
+    "gatsby-remark-copy-linked-files": "^6.13.2",
     "gatsby-remark-external-links": "0.0.4",
-    "gatsby-remark-images": "^7.13.1",
+    "gatsby-remark-images": "^7.13.2",
     "gatsby-remark-images-medium-zoom": "^1.7.0",
-    "gatsby-remark-prismjs": "^7.13.1",
-    "gatsby-remark-responsive-iframe": "^6.13.1",
+    "gatsby-remark-prismjs": "^7.13.2",
+    "gatsby-remark-responsive-iframe": "^6.13.2",
     "gatsby-remark-smartypants": "^6.13.1",
     "gatsby-source-filesystem": "^5.13.1",
     "gatsby-transformer-remark": "^6.13.1",