Correct spelling mistakes (#1163)

Co-authored-by: collerek <collerek@gmail.com>

docs/transactions.md

@@ -8,7 +8,7 @@ To use transactions use `database.transaction` as async context manager:
 
 ```python
 async with database.transaction():
-    # everyting called here will be one transaction
+    # everything called here will be one transaction
     await Model1().save()
     await Model2().save()
     ...
@@ -85,4 +85,4 @@ async def sample_test():
         async with database.transaction(force_rollback=True):
             # your test code here
             ...
-```
+```