This commit adds initial support for ".npmrc" files.
Currently we only discover ".npmrc" files next to "package.json" files
and discovering these files in user home dir is left for a follow up.
This pass supports "_authToken" and "_auth" configuration
for providing authentication.
LSP support has been left for a follow up PR.
Towards https://github.com/denoland/deno/issues/16105
This commit updates our testing npm registry to handle
additional `@denotest2` scope in addition to `@denotest`
scope. I might have to update it further in the future to handle
additional scopes, but it's good enough for now.
