test: Expose set and getVariable in Cypress tests

Partial cherry pick of 4a90d5328

Signed-off-by: Louis Chemineau <louis@chmn.me>

cypress.config.ts

@@ -68,6 +68,19 @@ export default defineConfig({
 
 			on('task', { removeDirectory })
 
+			// This allows to store global data (e.g. the name of a snapshot)
+			// because Cypress.env() and other options are local to the current spec file.
+			const data = {}
+			on('task', {
+				setVariable({ key, value }) {
+					data[key] = value
+					return null
+				},
+				getVariable({ key }) {
+					return data[key] ?? null
+				},
+			})
+
 			// Disable spell checking to prevent rendering differences
 			on('before:browser:launch', (browser, launchOptions) => {
 				if (browser.family === 'chromium' && browser.name !== 'electron') {