Terminals/profiles/icon only supports codicon

[jrieken]

Testing #127194

In the package.json I am only allowed to define an icon via codicons, not as path. We should as this aligns it with commands/icon and the vscode.d.ts definition of icons

[jrieken]

definition of command icons:

vscode/src/vs/workbench/api/common/menusExtensionPoint.ts

Lines 545 to 563 in 9510b91

	icon: {
	description: localize({ key: 'vscode.extension.contributes.commandType.icon', comment: ['do not translate or change `\\$(zap)`, \\ in front of $ is important.'] }, '(Optional) Icon which is used to represent the command in the UI. Either a file path, an object with file paths for dark and light themes, or a theme icon references, like `\\$(zap)`'),
	anyOf: [{
	type: 'string'
	},
	{
	type: 'object',
	properties: {
	light: {
	description: localize('vscode.extension.contributes.commandType.icon.light', 'Icon path when a light theme is used'),
	type: 'string'
	},
	dark: {
	description: localize('vscode.extension.contributes.commandType.icon.dark', 'Icon path when a dark theme is used'),
	type: 'string'
	}
	}
	}]
	}

[Tyriar]

Let's push this as it's a little too involved than we're comfortable with at this stage in endgame.