feat(date): introduce faker.defaultRefDate and setDefaultRefDate

[ST-DDT]

Fixes #859

• Fixes feat(date): introduce global refDate instead of passing it every time #859
• Unblocks infra(docs): add docs diff script #1755

This PR introduces the faker.setDefaultRefDate method, that can be used to configure the default refDate fallback value.

• fakerjs.dev: (will update when the next release is created)
• next.fakerjs.dev: (will update when the next PR is merged)
• dev: (and it will stay like this)

---

I'm not very happy with both the name and implementation.

• For the name, I also considered refDateFallbackSource.
• For the implementation, I considered adding it directly to the date module, but then I would need to pass the fallback to the toDate function that is located outside.
  • Adding it directly to the DateModule would complicate Faker.fork and Faker.derive.
  • Adding toDate to the module directly causes some issues as well (IIRC)
  • My current approach is adding this as MVP and then move these kind of configs to fakerCore.config{dateRefDateFallbackSource, helpersUniqueFallbackStore, ...} or something similar. That way, it can share or not share these things between faker instances, configure it globally or per method (it's bound fakerCore)
• I'm unsure how I can document the Defaults to `refDateSource()`. in an easier to understand way.

Any feedback or suggestions are welcome!

[codecov]

Codecov Report

Merging #1757 (4fa1a23) into next (28a9848) will increase coverage by 0.00%.
The diff coverage is 100.00%.

Additional details and impacted files

@@           Coverage Diff           @@
##             next    #1757   +/-   ##
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  Coverage   99.64%   99.64%           
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  Files        2340     2340           
  Lines      242624   242653   +29     
  Branches     1103     1110    +7     
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+ Hits       241772   241801   +29     
  Misses        831      831           
  Partials       21       21           

Impacted Files	Coverage Δ
src/faker.ts	95.48% <100.00%> (+0.36%)	⬆️
src/modules/date/index.ts	99.79% <100.00%> (+<0.01%)	⬆️
src/modules/git/index.ts	100.00% <100.00%> (ø)

[Shinigami92]

I think refDateSource or defaultRefDate is a good name
I didn't thought enough yet, but the idea with having a faker.config sounds good to me 🤔 (later PR / iteration)

But I would like to have (for now) a faker.defaultRefDate
Not sure if we already want to mix it together with "tree-shakable" "global-faker-npm-module" ideas yet

IMO for now it should be next to faker.seed like the issue author mentioned

• feat(date): introduce global refDate instead of passing it every time #859