internal/worker: add standard library keywords
internal/worker: add standard library keywords

Add keywords in the reference data that would identify a CVE as a Go
vulnerability data are added.

Change-Id: I5e237486dd7e2a56acb41706b523d3f036cbe53e
Reviewed-on: https://go-review.googlesource.com/c/vuln/+/362240
Trust: Julie Qiu <8d32267b6b4884cf35adeaccde2b6857ae11aace@golang.org>
Run-TryBot: Julie Qiu <8d32267b6b4884cf35adeaccde2b6857ae11aace@golang.org>
TryBot-Result: Go Bot <66cb808b70d30c07676d5e946fee83fd561249e5@golang.org>
Reviewed-by: Jonathan Amsterdam <e3d3698b2ccd5955e4adf250d0785062d0f9018b@google.com>

golang/vuln,golang/vuln