Add blurb to web about onboarding emails

packages/web/components/templates/auth/EmailSignup.tsx

@@ -186,6 +186,17 @@ export function EmailSignup(): JSX.Element {
           </Button>
         </HStack>
 
+        <StyledText
+          style="action"
+          css={{
+            color: '$omnivoreLightGray',
+            textAlign: 'center',
+          }}
+        >
+          During our beta period Omnivore will send you daily tips for your
+          first week as a new user. If you don't like them you can unsubscribe.
+        </StyledText>
+
         <StyledText
           style="action"
           css={{