feat: add support for baseUrl in options

[JustinBeckwith]

The GaxiosOptions object now supports a baseUrl property that can be used to set the base url for a request. This is especially useful when using a single instance, and making many requests to the same domain:

const gaxios = require('gaxios');
gaxios.instance.defaults.baseUrl = 'https://example.com';
gaxios.request({ url: '/data' }).then(...);

[codecov]

Codecov Report

Merging #19 into master will increase coverage by 0.12%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master      #19      +/-   ##
==========================================
+ Coverage    90.6%   90.72%   +0.12%     
==========================================
  Files           4        4              
  Lines         149      151       +2     
  Branches       51       52       +1     
==========================================
+ Hits          135      137       +2     
  Misses         14       14

Impacted Files	Coverage Δ
src/common.ts	100% <ø> (ø)	⬆️
src/gaxios.ts	83.13% <100%> (+0.41%)	⬆️

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[JustinBeckwith]

🎉 This PR is included in version 1.1.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.