Guidance Cards - Snapshot tests to harden visual outputs.

[vincethecoder]

Add snapshot tests for the following component outputs:

1. Basic visual representation of instructions on a guidance card.

2. Compounded visual representation of instructions on a guidance card.
   i. Next Banner instructions
   ii. Lane Indications

/cc @mapbox/navigation-ios

[1ec5]

Snapshot tests have been added to #2149.