Fix date string display in service alert

[landonreed]

Use the correct moment method to format date string.

Fix ibi-group/trimet-mod-otp#136.

[codecov-io]

Codecov Report

Merging #94 into dev will not change coverage.
The diff coverage is 0%.

@@          Coverage Diff          @@
##             dev     #94   +/-   ##
=====================================
  Coverage   10.2%   10.2%           
=====================================
  Files        134     134           
  Lines       5999    5999           
  Branches    1733    1733           
=====================================
  Hits         612     612           
  Misses      4567    4567           
  Partials     820     820

Impacted Files	Coverage Δ
...components/narrative/line-itin/transit-leg-body.js	0% <0%> (ø)	⬆️

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[evansiroky]

🎉 This PR is included in version 0.12.3 🎉

The release is available on:

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

Your semantic-release bot 📦🚀

[msrichardson]

To clarify, if service alert effective date is anything other than yesterday/today/tomorrow (or now +/- one day), please use the actual date (ex: Effective as of August 6, 2019). If yesterday/today/tomorrow (now +/- one day), please use that language (ex: Effective as of 2:33 pm today). [We don't anticipate ever having a 'tomorrow', but wanted to include that possibility for other entities.]