Fix datetimes on tooltips

Closes #14206 

Updates tooltip datetimes on `.timeago()` instances. 

**Inline notes**

![Screen_Shot_2016-04-07_at_1.25.12_PM](/uploads/2f55390a7e91dabf75e71fe3bda91849/Screen_Shot_2016-04-07_at_1.25.12_PM.png)

**Existing and new notes**

![Screen_Shot_2016-04-07_at_1.24.49_PM](/uploads/202bb7476738eb048f2d94abb68174e7/Screen_Shot_2016-04-07_at_1.24.49_PM.png)


**Issuable dates**

![Screen_Shot_2016-04-07_at_1.24.32_PM](/uploads/80fd5cc3c06fade0b1c615bc7b7611a8/Screen_Shot_2016-04-07_at_1.24.32_PM.png)

**Build dates**

![Screen_Shot_2016-04-07_at_1.25.02_PM](/uploads/832f43284005ea610a3ad54a49b97104/Screen_Shot_2016-04-07_at_1.25.02_PM.png)

See merge request !3497