Re-export ApiError from google-cloud/common to ease usage downstream

[MasterOdin]

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In our code, we want to check if an error that's returned by the BQ library is an ApiError, and if so, we want to re-use properties off it.

Within our code, we have something like this for getting a user's datasets:

import { BigQuery } from '@google-cloud/bigquery';
import { ApiError } from '@google-cloud/common';

client = new BigQuery({ /* options */ });

// ....

client
  .getDatasets()
  .then(([datasets]) => {
    // do something with the datasets
  })
  .catch((e) => {
    if (e instanceof ApiError) {
      if (e.code === 403 || e.code === 404) {
        // show user permission error
      }
    }
    // show user generic error message
  });

where to make the instanceof ApiError check work, we were adding @google-cloud/common to our dependencies and importing from there. We ended up with a bug where @google-cloud/bigquery got updated and so the version of @google-cloud/common in our dependencies no longer matched what @google-cloud/bigquery used, and the instanceof ApiError check now failed.

Describe the solution you'd like
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It'd be nice if @google-cloud/bigquery re-exported ApiError so that the above code snippet could be rewritten as :

import { ApiError, BigQuery } from '@google-cloud/bigquery';

client = new BigQuery({ /* options */ });

// ....

client
  .getDatasets()
  .then(([datasets]) => {
    // do something with the datasets
  })
  .catch((e) => {
    if (e instanceof ApiError) {
      if (e.code === 403 || e.code === 404) {
        // show user permission error
      }
    }
    // show user generic error message
  });

and then the instanceof check will never fail.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

We could remove @google-cloud/common from our dependency list, and rely on it being available implicitly via how node_modules works, but that seems risky, and we could end up with being broken still depending on how yarn decides to hoist things. We've also looked to use duck typing, but that gives us less type strength.

Additional context
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[loferris]

@MasterOdin I've re-exported the whole google-common package, which might make coding a bit more verbose, but will help us hopefully avoid having to do this piecemeal.