Synonym for regex -> regular expression

[steve-fenton-octopus]

We use "regular expression" in docs, so searches for "regex" won't find matches.

This synonym will make regex searches find the regular expression results.

Additional information.

We mention "regular expressions" but people will definitely search for "regex".
The serverless search has a synonym feature we can use to tackle situations like this.

Here's a synonym for regex: 'regular expression'

Note

Astro Accelerator is updated through a pnpm script, but our microsites are no longer connected to the accelerator in this way (it has been turned into a copy). When you read the Accelerator docs, bear in mind our microsites might not be up to date with features and changes.

[samwld]

LGTM