Wrap form data and await form to fix mypy issues in amazon provider

[bugraoz93]

Main Canary Run: https://github.com/apache/airflow/actions/runs/27970332910/job/82777675902

Error:

    providers/amazon/src/airflow/providers/amazon/aws/auth_manager/routes/login.py:104: error: Need type annotation for "form_data"  [var-annotated]
            form_data = anyio.from_thread.run(request.form)
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    providers/amazon/src/airflow/providers/amazon/aws/auth_manager/routes/login.py:104: error: Argument 1 to "run" has incompatible type
    "def form(self, *, max_files: int | float = ..., max_fields: int | float = ..., max_part_size: int = ...) -> AwaitableOrContextManager[FormData]"; expected "Callable[[], Coroutine[Any, Any, Never]]" 
    [arg-type]
            form_data = anyio.from_thread.run(request.form)
                                              ^~~~~~~~~~~~
    providers/amazon/src/airflow/providers/amazon/aws/auth_manager/routes/login.py:154: error: Need type annotation for "form_data"  [var-annotated]
            form_data = anyio.from_thread.run(request.form)
                        ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    providers/amazon/src/airflow/providers/amazon/aws/auth_manager/routes/login.py:154: error: Argument 1 to "run" has incompatible type
    "def form(self, *, max_files: int | float = ..., max_fields: int | float = ..., max_part_size: int = ...) -> AwaitableOrContextManager[FormData]"; expected "Callable[[], Coroutine[Any, Any, Never]]" 
    [arg-type]
            form_data = anyio.from_thread.run(request.form)
                                              ^~~~~~~~~~~~
    Found 4 errors in 1 file (checked 4582 source files)

What changed?

• FormData imported under if TYPE_CHECKING: (satisfies ruff TC002).
• TYPE_CHECKING added to the typing import.
• _read_form(request) helper wrapping request.form() in a real coroutine — fixes both mypy errors (var-annotated + arg-type) with no type: ignore.
• Both call sites use _read_form(request).

---

Was generative AI tooling used to co-author this PR?

• Yes (please specify the tool below)
  Claude Opus 4.8

---

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[vincbeck]

What does it solve?

[bugraoz93]

What does it solve?

Sorry for the missing description! Updating..
It fixes some problem here, we can define as var: FormData but that still not solving all issues
https://github.com/apache/airflow/actions/runs/27970332910/job/82777675902

[bugraoz93]

Description has been updated. I initially cast with var: FormData, then checked with Claude. We can put ignore as well @vincbeck

[SameerMesiah97]

What does it solve?

The issue is breaking main. I ran into this exact CI failure in PR #68775 .

[seanghaeli]

Running into the same CI failures

[SameerMesiah97]

Looks like you have addressed both lines of code causing the MyPy checks to fail. Approved pending green CI.