fix(volume): improve definition of cubic yards conversion factor (#695)

Author: mhink

package.json

@@ -99,7 +99,7 @@
 		},
 		{
 			"gzip": true,
-			"limit": "6.67 KB",
+			"limit": "6.68 KB",
 			"path": "./dist/index.mjs"
 		}
 	]

src/conversions/measures/volume.ts

@@ -28,7 +28,7 @@ export const volume: Measure = {
 		// https://en.wikipedia.org/wiki/Acre-foot
 		{ names: ['acre-foot', 'acre-feet'], symbols: ['ac⋅ft', 'ac ft'], ratio: 1233.481_837_547_52 },
 		// https://en.wikipedia.org/wiki/Cubic_yard
-		{ names: ['cubic yard', 'cubic yards'], symbols: ['cu yd', 'yd3', 'yd³'], ratio: 0.76 },
+		{ names: ['cubic yard', 'cubic yards'], symbols: ['cu yd', 'yd3', 'yd³'], ratio: 0.764_554_857_984 },
 		// https://en.wikipedia.org/wiki/Cubic_foot
 		{ names: ['cubic foot', 'cubic feet'], symbols: ['cu ft', 'ft3', 'ft³'], ratio: 0.028_316_846_592 },
 		{ names: ['board foot', 'board feet'], ratio: 0.002_359_737 },

src/converters/conversions/volume.test.ts

@@ -17,6 +17,8 @@ describe('conversions', () => {
 		{ from: [1, 'Pm3'], to: [1e45, 'm3'] },
 
 		{ from: [1, 'ft3'], to: [0.028_316_846_592, 'm3'] },
+		{ from: [1, 'yd3'], to: [0.764_554_857_984, 'm3'] },
+		{ from: [27, 'ft3'], to: [1, 'yd3'] },
 
 		{ from: [1, 'US legal cup'], to: [240 + 0.000_000_000_000_03, 'mL'] },
 	]);