emoji_eventsRun-length encoding

Write two functions:

• encode(text) turns runs of the same character into count + character: "aaabcc" becomes "3a1b2c".
• decode(data) reverses it: "3a1b2c" becomes "aaabcc". Counts can have several digits ("12x").

Acceptance criteria

• decode(encode(s)) == s for any text without digits.
• Empty input gives empty output.
• The tests at the bottom print All tests passed.