fix some of mypy complaints.

lnbits/extensions/bleskomat/crud.py

@@ -106,7 +106,7 @@ async def create_bleskomat_lnurl(
     return bleskomat_lnurl
 
 
-async def get_bleskomat_lnurl(secret: str) -> BleskomatLnurl:
+async def get_bleskomat_lnurl(secret: str) -> Optional[BleskomatLnurl]:
     hash = generate_bleskomat_lnurl_hash(secret)
     row = await db.fetchone("SELECT * FROM bleskomat_lnurls WHERE hash = ?", (hash,))
     return BleskomatLnurl(**row) if row else None

lnbits/extensions/bleskomat/models.py

@@ -91,8 +91,8 @@ class BleskomatLnurl(NamedTuple):
                         wallet_id=self.wallet,
                         payment_request=query["pr"],
                     )
-                except Exception as exc:
-                    raise LnurlValidationError(f"Failed to pay invoice: {exc.message}")
+                except Exception:
+                    raise LnurlValidationError("Failed to pay invoice")
                 if not payment_hash:
                     raise LnurlValidationError("Failed to pay invoice")