us-interstate icons with ref_length > 3

[nickpeihl]

The highway-shield-us-interstate layer looks for ref_length >= 6 and assigns the icon-image that translates to us_interstate_{ref_length}. But we don't have icons for us-interstate_4, us-interstate_5, and us-interstate_6.

osm-bright-gl-style/style.json

Lines 2522 to 2551 in 500e26e

	"filter": ["all", ["<=", "ref_length", 6],
	["==", "$type", "LineString"],
	["in", "network", "us-interstate"]
	],
	"id": "highway-shield-us-interstate",
	"layout": {
	"icon-image": "{network}_{ref_length}",
	"icon-rotation-alignment": "viewport",
	"icon-size": 1,
	"symbol-placement": {
	"base": 1,
	"stops": [
	[7, "point"],
	[7, "line"],
	[8, "line"]
	]
	},
	"symbol-spacing": 200,
	"text-field": "{ref}",
	"text-font": ["Noto Sans Regular"],
	"text-rotation-alignment": "viewport",
	"text-size": 10
	},
	"minzoom": 7,
	"paint": {
	"text-color": "rgba(0, 0, 0, 1)"
	},
	"source": "openmaptiles",
	"source-layer": "transportation_name",
	"type": "symbol"

However, I don't expect there are any us-interstate networks with a ref_length > 3. So would it make sense to update this filter as such instead of creating new icons?

-"filter": ["all", ["<=", "ref_length", 6], 
+"filter": ["all", ["<=", "ref_length", 3], 
   ["==", "$type", "LineString"], 
   ["in", "network", "us-interstate"] 
 ]

[ZeLonewolf]

Interstate H201 in Hawaii is 4 digits.