The CODEQL_WRAPPER environment variable will be set to "action" if
running in an actions context and "runner" otherwise. This variable
will be used in the cli to determine which context it is in.
Also, use a similar mechanism to provide a different user agent
when communicating with the github api.
* Allow the codeql-action to be run locally
This change allows the codeql-action to be run locally through
[act](https://github.com/nektos/act).
In order to run the action locally, you need to do two things:
1. Add the `CODEQL_LOCAL_RUN: true` environment variable. The only way
I could figure out how to do this was to add it directly in the
workflow file in an `env` block. It _should_ be possible to add it
through a `.env` file and pass it to `act`, but I couldn't get it
working.
2. Run this command `act -j codeql -s GITHUB_TOKEN=<MY_PAT>`
Setting the `CODEQL_LOCAL_RUN` env var will fill in missing env vars
that the action needs, but isn't set by `act`. It will also avoid
making api calls to github that would fail locally.
This is a refactoring discussed in
https://github.com/github/dsp-codeql/issues/36