chore: update markdown formatting for v3 mdx parser

[dfx-json]

The portal will soon be upgraded to Docusaurus v3. In order to successfully compile, submodules must conform to mdx v3 parsing rules.

This PR updates the formatting to use backticks whenever possible, and escapes { with a backslash.

[github-actions[bot]]

🤖 Here's your preview: https://p3j7v-5yaaa-aaaak-qckka-cai.icp0.io/docs

[mraszyk]

Could you please also add a CI check for the new formatting? Otherwise, we're likely to deviate again pretty soon.

[dfx-json]

@mraszyk would upgrading the docusaurus version (see https://github.com/dfinity/interface-spec/pull/297) used in the interface-spec repo suffice? It's not clear to me what CI checks could be added to enforce proper formatting.

[dfx-json]

closing in favor of pursuing #297