Cast GitHub app_id as string before using as iss

[8R0WNI3]

The PyJWT library expects the issuer to be of type str and enforces it with jpadilla/pyjwt#1040. Using an integer as done before will result in TypeError: Issuer (iss) must be a string..

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Version Information

• The version of Python you're using: Python 3.13.9

• The version of pip you used to install github3.py: pip 25.3

• The version of github3.py, requests, uritemplate, and python-dateutil installed: github3.py 4.0.1

Minimum Reproducible Example

import cryptography.hazmat.primitives.asymmetric.rsa as rsa
import cryptography.hazmat.primitives.serialization as serialization
import github3.apps


private_key = rsa.generate_private_key(
    public_exponent=65537,
    key_size=2048,
)

private_key_pem = private_key.private_bytes(
    encoding=serialization.Encoding.PEM,
    format=serialization.PrivateFormat.PKCS8,
    encryption_algorithm=serialization.NoEncryption(),
)

github3.apps.create_token(
    private_key_pem=private_key_pem,
    app_id=12345,
)

Exception information

Traceback (most recent call last):
  File "<python-input-3>", line 1, in <module>
    github3.apps.create_token(
    ~~~~~~~~~~~~~~~~~~~~~~~~~^
        private_key_pem=private_key_pem,
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
        app_id=12345,
        ^^^^^^^^^^^^^
    )
    ^
  File "/opt/homebrew/lib/python3.13/site-packages/github3/apps.py", line 175, in create_token
    token = jwt.encode(
        payload={"iat": now, "exp": now + expire_in, "iss": app_id},
        key=private_key_pem,
        algorithm="RS256",
    )
  File "/opt/homebrew/lib/python3.13/site-packages/jwt/api_jwt.py", line 145, in encode
    raise TypeError("Issuer (iss) must be a string.")
TypeError: Issuer (iss) must be a string.

[8R0WNI3]

Fixes #1306.

[nebojsa-prodana]

Hello, sorry for barging in. Do we know when this will be getting released?