Fixed debug_headers type hints for WorkspaceClient and AccountClient (#258)

## Changes
Change `debug_headers` type hint from `int` to `bool`.

According to the docs it should be `bool`:

https://github.com/databricks/databricks-sdk-py/blob/519fbe37b661d29df2acdd7880484b58f43d7e9a/README.md?plain=1#L235

https://github.com/databricks/databricks-sdk-py/blob/519fbe37b661d29df2acdd7880484b58f43d7e9a/docs/authentication.md?plain=1#L134


## Tests
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How is this tested? Please see the checklist below and also describe any
other relevant tests
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- [x] `make test` run locally
- [x] `make fmt` applied
- [ ] relevant integration tests applied --> Not applicable, no logic
change

Author: alex7c4

.codegen/__init__.py.tmpl

@@ -36,7 +36,7 @@ def _make_dbutils(config: client.Config):
 class WorkspaceClient:
     def __init__(self, *{{range $args}}, {{.}}: str = None{{end}},
                  debug_truncate_bytes: int = None,
-                 debug_headers: int = None,
+                 debug_headers: bool = None,
                  product="unknown",
                  product_version="0.0.0",
                  credentials_provider: client.CredentialsProvider = None,
@@ -58,7 +58,7 @@ class WorkspaceClient:
 class AccountClient:
     def __init__(self, *{{range $args}}, {{.}}: str = None{{end}},
                  debug_truncate_bytes: int = None,
-                 debug_headers: int = None,
+                 debug_headers: bool = None,
                  product="unknown",
                  product_version="0.0.0",
                  credentials_provider: client.CredentialsProvider = None,