REST: Remove spec-version version HTTP header (#2358)

# Rationale for this change

This was added way ago, but I don't think it makes any sense for two
reasons:

- It was never updated properly :)
- The spec is not versioned with the Java release

Better to clean this up


# Are these changes tested?

# Are there any user-facing changes?

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Author: Fokko

pyiceberg/catalog/rest/__init__.py

@@ -80,8 +80,6 @@
 if TYPE_CHECKING:
     import pyarrow as pa
 
-ICEBERG_REST_SPEC_VERSION = "0.14.1"
-
 
 class Endpoints:
     get_config: str = "config"
@@ -485,7 +483,6 @@ def _config_headers(self, session: Session) -> None:
         header_properties = get_header_properties(self.properties)
         session.headers.update(header_properties)
         session.headers["Content-type"] = "application/json"
-        session.headers["X-Client-Version"] = ICEBERG_REST_SPEC_VERSION
         session.headers["User-Agent"] = f"PyIceberg/{__version__}"
         session.headers.setdefault("X-Iceberg-Access-Delegation", ACCESS_DELEGATION_DEFAULT)
 

tests/catalog/test_rest.py

@@ -59,7 +59,6 @@
 
 TEST_HEADERS = {
     "Content-type": "application/json",
-    "X-Client-Version": "0.14.1",
     "User-Agent": f"PyIceberg/{pyiceberg.__version__}",
     "Authorization": f"Bearer {TEST_TOKEN}",
     "X-Iceberg-Access-Delegation": "vended-credentials",