Allow artifact retention to be configured

- Default to retaining uploaded artifacts for 7 days.
- Add a parameter to allow this to be configured.

test/jest/input-params.test.ts

@@ -0,0 +1,22 @@
+import * as inputParams from '../../src/input-params'
+
+describe('input params', () => {
+    describe('parses numeric input', () => {
+        it('uses default value', () => {
+            const val = inputParams.parseNumericInput('param-name', '', 88)
+            expect(val).toBe(88)
+        })
+        it('parses numeric input', () => {
+            const val = inputParams.parseNumericInput('param-name', '34', 88)
+            expect(val).toBe(34)
+        })
+        it('fails on non-numeric input', () => {
+            const t = () => {
+                inputParams.parseNumericInput('param-name', 'xyz', 88)
+            };
+
+            expect(t).toThrow(TypeError)
+            expect(t).toThrow("The value 'xyz' is not a valid numeric value for 'param-name'.")
+        })
+    })
+})