fix: don't default to localhost in production

[galvez]

Noticed a live deployment with @nuxt/http was using localhost if no environment variable was set.

[codecov-io]

Codecov Report

Merging #72 into dev will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##              dev      #72   +/-   ##
=======================================
  Coverage   97.05%   97.05%           
=======================================
  Files           1        1           
  Lines          34       34           
  Branches       16       16           
=======================================
  Hits           33       33           
  Misses          1        1

Impacted Files	Coverage Δ
lib/module.js	97.05% <100%> (ø)	⬆️

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[galvez]

@pi0 erm, still needs a fix -- wait :)

[galvez]

K, fixed it.

[galvez]

Related: nuxt/press#58 -- actually @pi0 would appreciate if you could double check and make sure this is really the issue.

[pi0]

0.0.0.0 is not a valid IP. Maybe we can use this.options.server.host which handles --host as well.

See related PR for axios module: nuxt-community/axios-module#245

[pi0]

/reminder @galvez What do you think about proposed change?

[galvez]

Let's do that :)

[pi0]

Suggestion applied by bc58738. Implementation is now consistent with axios module to support CLI flags or nuxt config if provided.