fix(Email Queue): change fieldtype of shown_as_cc

This is done to allow more number of recipients to be CCed in
the email. The existing fieldtype was Data, which had a
restriction of 140 characters, thereby allowing only a few email
addresses to be CCed. It has now been changed to Small Text, to
incorporate more email addresses.

Co-authored-by: sahil28297 <37302950+sahil28297@users.noreply.github.com>
Signed-off-by: Ameya Shenoy <shenoy.ameya@gmail.com>

frappe/email/doctype/email_queue/test_email_queue.js

@@ -0,0 +1,23 @@
+/* eslint-disable */
+// rename this file from _test_[name] to test_[name] to activate
+// and remove above this line
+
+QUnit.test("test: Email Queue", function (assert) {
+	let done = assert.async();
+
+	// number of asserts
+	assert.expect(1);
+
+	frappe.run_serially([
+		// insert a new Email Queue
+		() => frappe.tests.make('Email Queue', [
+			// values to be set
+			{key: 'value'}
+		]),
+		() => {
+			assert.equal(cur_frm.doc.key, 'value');
+		},
+		() => done()
+	]);
+
+});