docs: Update Maestro Example

[Moti2002]

change this example:
from ai21 import AI21Client

client = AI21Client()

run_result = client.beta.maestro.runs.create_and_poll(
input="Write a poem about the ocean",
requirements=[
{
"name": "length requirement",
"description": "The length of the poem should be less than 1000 characters",
},
{
"name": "rhyme requirement",
"description": "The poem should rhyme",
},
],
include=["requirements_result"]
)

to this example:
+# Create and poll a Maestro run
+run_result = client.beta.maestro.runs.create_and_poll(

• input="Tell me about AI21 Maestro",
• requirements=[

•    {
  

•        "name": "length requirement",
  

•        "description": (
  

•            "The length of the response should be less than "
  

•            "2000 characters"
  

•        ),
  

•    },
  

•    {
  

•        "name": "source requirement",
  

•        "description": (
  

•            "Should rely on information from these websites: "
  

•            "https://www.ai21.com/, https://www.ai21.com/maestro/, "
  

•            "https://docs.ai21.com/home"
  

•        ),
  

•    },
  

• ],
• include=["requirements_result"] # Include additional fields in the result
  +)

+# Output the result
+print("\n=== AI21 MAESTRO INFO ===")
+print(run_result.result)
+print()