Use repr for error logging (#1711)

Follow-up on #1708
([comment](#1708 (comment)))

As mentioned there, there is a `__repr__` but not a `__str__`, leading
to an empty log message (for HTTPExceptions).

An example when running the dev server (previously the first line would
just be an empty line):
```
HTTPException(status_code=404, detail='Not Found')
INFO:     127.0.0.1:33538 - "GET /swaggers/ui/ HTTP/1.1" 404 Not Found
```

However, I would also be fine with just removing the logging here as
`HTTPException`s can be part of the normal flow, without indicating an
actual application error (case in point: raising a `Not Found`
exception)

connexion/middleware/exceptions.py

@@ -1,7 +1,9 @@
 import logging
 
-from starlette.exceptions import ExceptionMiddleware as StarletteExceptionMiddleware
 from starlette.exceptions import HTTPException
+from starlette.middleware.exceptions import (
+    ExceptionMiddleware as StarletteExceptionMiddleware,
+)
 from starlette.requests import Request as StarletteRequest
 from starlette.responses import Response
 from starlette.types import ASGIApp, Receive, Scope, Send
@@ -22,7 +24,7 @@ def __init__(self, next_app: ASGIApp):
 
     @staticmethod
     def problem_handler(_request: StarletteRequest, exc: ProblemException):
-        logger.error(exc)
+        logger.error("%r", exc)
 
         response = exc.to_problem()
 
@@ -35,7 +37,7 @@ def problem_handler(_request: StarletteRequest, exc: ProblemException):
 
     @staticmethod
     def http_exception(_request: StarletteRequest, exc: HTTPException) -> Response:
-        logger.error(exc)
+        logger.error("%r", exc)
 
         headers = exc.headers
 
@@ -52,7 +54,7 @@ def http_exception(_request: StarletteRequest, exc: HTTPException) -> Response:
 
     @staticmethod
     def common_error_handler(_request: StarletteRequest, exc: Exception) -> Response:
-        logger.error(exc, exc_info=exc)
+        logger.error("%r", exc, exc_info=exc)
 
         response = InternalServerError().to_problem()