fix requirements.txt

remove reduntdant version that breaks pip
```
 => ERROR [stage-2  5/18] RUN pip install -r requirements.txt                                                                                           2.2s
------
 > [stage-2  5/18] RUN pip install -r requirements.txt:
#0 1.825 ERROR: Invalid requirement: 'sqlalchemy[asyncio]~=1.4.39 <2.0' (from line 10 of requirements.txt)
#0 2.055 WARNING: You are using pip version 21.2.4; however, version 23.0.1 is available.
```

api/requirements.txt

@@ -7,7 +7,7 @@ motor~=3.0.0
 pyyaml<6
 -e git+https://github.com/openmaptiles/openmaptiles-tools#egg=openmaptiles-tools
 sqlparse~=0.4.2
-sqlalchemy[asyncio]~=1.4.39 <2.0
+sqlalchemy[asyncio]~=1.4.39
 asyncpg~=0.24.0
 pyshp~=2.3.1
 alembic~=1.7.7