Remove .drone.yml

I stopped using drone last year.

.drone.yml

@@ -1,43 +0,0 @@
----
-kind: pipeline
-type: docker
-name: python310
-
-steps:
-- name: build
-  image: python:3.10-slim
-  commands:
-  - id
-  - python -V
-  - apt update && apt install -y gcc g++ libicu-dev pkg-config git
-  - pip install -r requirements-dev.txt
-
----
-kind: pipeline
-type: docker
-name: python39
-
-steps:
-- name: build
-  image: python:3.9-slim
-  commands:
-  - id
-  - python -V
-  - apt update && apt install -y gcc g++ libicu-dev pkg-config git
-  - pip install -r requirements-dev.txt
-
----
-kind: pipeline
-type: docker
-name: python38
-
-steps:
-- name: build
-  image: python:3.8-slim
-  commands:
-  - id
-  - python -V
-  - apt update && apt install -y gcc g++ libicu-dev pkg-config git
-  - pip install -r requirements-dev.txt
-
-# vim: ts=2 sw=2 et