gatsby-plugin-mdx JSON5 invalid end of input

[sh0rez]

Description

Trying to build my gatbsy-docz project, sporadically fails with this error message:

10:49:16 PM: $ gatsby build
10:49:19 PM: warning Configuring yargs through package.json is deprecated and will be removed in the next major release, please use the JS API instead.
10:49:19 PM: success open and validate gatsby-configs - 1.271s
10:49:20 PM: success load plugins - 0.394s
10:49:20 PM: success onPreInit - 0.001s
10:49:20 PM: success delete html and css files from previous builds - 0.012s
10:49:20 PM: success initialize cache - 0.007s
10:49:20 PM: success copy gatsby files - 0.030s
10:49:21 PM: success onPreBootstrap - 0.906s
10:49:21 PM: success createSchemaCustomization - 0.001s
10:49:21 PM: warning Configuring yargs through package.json is deprecated and will be removed in the next major release, please use the JS API instead.
10:49:26 PM: error "gatsby-plugin-mdx" threw an error while running the onCreateNode lifecycle:
10:49:26 PM: JSON5: invalid end of input at 1:1
10:49:26 PM: 
10:49:26 PM:   SyntaxError: JSON5: invalid end of input at 1:1
10:49:26 PM:   
10:49:26 PM:   - parse.js:1083 syntaxError
10:49:26 PM:     [docs]/[json5]/lib/parse.js:1083:17
10:49:26 PM:   
10:49:26 PM:   - parse.js:1032 invalidEOF
10:49:26 PM:     [docs]/[json5]/lib/parse.js:1032:12
10:49:26 PM:   
10:49:26 PM:   - parse.js:821 Object.start
10:49:26 PM:     [docs]/[json5]/lib/parse.js:821:19
10:49:26 PM:   
10:49:26 PM:   - parse.js:32 Object.parse
10:49:26 PM:     [docs]/[json5]/lib/parse.js:32:32
10:49:26 PM:   
10:49:26 PM:   - utils.js:78 requireJson
10:49:26 PM:     [docs]/[gatsby-remark-vscode]/src/utils.js:78:71
10:49:26 PM:   
10:49:26 PM:   - processExtension.js:6 processExtension
10:49:26 PM:     [docs]/[gatsby-remark-vscode]/src/processExtension.js:6:23
10:49:26 PM:   
10:49:26 PM:   - downloadExtension.js:30 syncExtensionData
10:49:26 PM:     [docs]/[gatsby-remark-vscode]/src/downloadExtension.js:30:38
10:49:26 PM:   
10:49:26 PM:   - downloadExtension.js:57 downloadExtension
10:49:26 PM:     [docs]/[gatsby-remark-vscode]/src/downloadExtension.js:57:9

Steps to reproduce

See this pull request: grafana/tanka#134, that's my source.

Basically gatsby, invoked using yarn build,

A failed CI build: https://app.netlify.com/sites/tanka/deploys/5dfbf0033d0e2c0008617c89

Expected result

It works everytime, or fails everytime

Actual result

It fails sometimes with above error message

Environment

  System:
    OS: Linux 5.4 Arch Linux
    CPU: (12) x64 Intel(R) Core(TM) i7-9750H CPU @ 2.60GHz
    Shell: 5.7.1 - /bin/zsh
  Binaries:
    Node: 13.3.0 - /usr/bin/node
    Yarn: 1.21.1 - /usr/bin/yarn
    npm: 6.12.1 - /usr/bin/npm
  Languages:
    Python: 3.8.0 - /usr/bin/python
  Browsers:
    Firefox: 71.0
  npmPackages:
    gatsby: ^2.18.12 => 2.18.12 
    gatsby-image: ^2.2.34 => 2.2.34 
    gatsby-remark-vscode: ^1.4.0 => 1.4.0 
    gatsby-theme-docz: ^2.3.0-alpha.5 => 2.3.0-alpha.5 
  npmGlobalPackages:
    gatsby-cli: 2.8.13

[sh0rez]

Not related to gatsby-plugin-mdx at all, this was failing because of vscode marketplace rate limiting experienced by the gatsby-remark-vscode plugin