[Gatsby] Migration to v5

[randychilau]

Description

This PR migrates the site from Gatsby v4 to v5 which requires React v18.

Update 09/20/2023: The latest package.json changes from the master branch can be seen here.

---

Additional Plugins Added/Updated:

• @fullcalendar/core: ^6.1.8
• @fullcalendar/daygrid: ^6.1.8
• @fullcalendar/google-calendar: ^6.0.2
• @fullcalendar/interaction: ^6.0.1
• @fullcalendar/react:^6.1.8
• babel-preset-gatsby:3.11.0
• dedent: 1.2.0
• gatsby-plugin-feed: 5.11.0
• gatsby-plugin-image: 3.11.0
• gatsby-plugin-manifest: 5.11.0
• gatsby-plugin-preload-fonts: 4.11.0
• gatsby-plugin-robots-txt: 1.8.0
• gatsby-plugin-sharp: 5.11.0
• gatsby-plugin-sitemap: 6.11.0
• gatsby-plugin-styled-components: 6.11.0
• gatsby-redirect-from: 1.0.4
• gatsby-source-filesystem: 5.11.0
• gatsby-transformer-sharp: 5.11.0
• gh-pages: 5.0.0
• prism-react-renderer: 2.0.6
• react-tabs: 6.0.2
• react-tooltip: 5.18.1
• rimraf: 5.0.1
• styled-components: 6.0.5
• swiper: 10.0.4

Plugins Removed (either not used as detected by depCheck or removed for redundancy with React 18 functionality):

• @sideway/address
• cytoscape-fcose
• deepmerge
• ~~gatsby-plugin-loadable-components-ssr~~
• joi
• react-honeycomb
• react-is
• react-scroll
• sharp

Notes for Reviewers It is temporarily required to install with npm install --legacy-peer-deps due to incompatibility with mdxv1 (a separate PR to be merged if/when this PR is merged).

A Github Page hosted preview is availalble here.

For plugins removed, please notify me if there is missing functionality due to removal.

Signed commits

• [x] Yes, I signed my commits.