Announce dropdown option text with screen reader (#318)

Description of changes

Updates `@microsoft/fast-foundation` package to acquire an [upstream bug fix](microsoft/fast#5467) that fixes an accessibility issue where dropdown options were not being announced by screen readers.

Author: hawkticehurst

README.md

@@ -25,12 +25,6 @@ Note that this doesn't change our recommendation of [avoiding the use of webview
 
 The Webview UI Toolkit is currently in a public preview with the goal of reaching `v1.0` sometime in Winter 2022.
 
-### Known issues
-
-Medium to high-visibility issues that are intended to be fixed with high priority.
-
--   Options within `vscode-dropdown` do not announce their text content on selection change [#181](https://github.com/microsoft/vscode-webview-ui-toolkit/issues/181)
-
 ## Getting started
 
 Follow the [Getting Started Guide](./docs/getting-started.md).

package-lock.json

@@ -31,7 +31,7 @@
 	},
 	"dependencies": {
 		"@microsoft/fast-element": "^1.6.0",
-		"@microsoft/fast-foundation": "^2.21.0"
+		"@microsoft/fast-foundation": "^2.30.0"
 	},
 	"devDependencies": {
 		"@babel/core": "^7.14.3",
@@ -49,8 +49,8 @@
 		"@storybook/addon-links": "^6.4.0-beta.4",
 		"@storybook/html": "^6.4.0-beta.4",
 		"@storybook/theming": "^6.4.0-beta.4",
-		"@typescript-eslint/eslint-plugin": "^2.23.0",
 		"@types/jest": "^26.0.20",
+		"@typescript-eslint/eslint-plugin": "^2.23.0",
 		"@vscode/codicons": "^0.0.22",
 		"babel-jest": "^27.2.4",
 		"babel-loader": "^8.2.2",