fix: allow custom Calcite CSS properties in style object type (#11051)

**Related Issue:** #11013

## Summary

Augments `csstype`'s module to allow all custom Calcite CSS properties
(step 3 from
https://github.com/frenic/csstype#what-should-i-do-when-i-get-type-errors).

---------

Co-authored-by: Max Patiiuk <[email protected]>

Author: jcfranco

packages/calcite-components/src/index.ts

@@ -7,6 +7,12 @@
 import { Runtime } from "@arcgis/lumina";
 import { setAssetPath as runtimeSetAssetPath } from "./runtime";
 
+declare module "csstype" {
+  interface Properties {
+    [index: `--calcite-${string}`]: any;
+  }
+}
+
 /** @internal */
 export let assetPathChanged = false;