feat: add artifacts and metadata outputs (#327)

Co-authored-by: CrazyMax <crazy-max@users.noreply.github.com>

src/context.ts

@@ -1,5 +1,6 @@
 import * as os from 'os';
 import * as core from '@actions/core';
+import {issueCommand} from '@actions/core/lib/command';
 
 export const osPlat: string = os.platform();
 export const osArch: string = os.arch();
@@ -21,3 +22,8 @@ export async function getInputs(): Promise<Inputs> {
     installOnly: core.getBooleanInput('install-only')
   };
 }
+
+// FIXME: Temp fix https://github.com/actions/toolkit/issues/777
+export function setOutput(name: string, value: any): void {
+  issueCommand('set-output', {name}, value);
+}