XSH-733: Enhance exec response and result

* add method to extract result headers (cut away boilerplate)
* add property to get response's dimension descriptors

Author: lupko

gooddata-sdk/gooddata_sdk/compute/model/execution.py

@@ -108,6 +108,11 @@ def is_complete(self, dim: int = 0) -> bool:
     def next_page_start(self, dim: int = 0) -> int:
         return self.paging_offset[dim] + self.paging_count[dim]
 
+    def get_all_headers(self, dim: int) -> list[list[Any]]:
+        header_groups = self.headers[dim]["headerGroups"]
+
+        return [[header for header in header_groups[idx]["headers"]] for idx in range(len(header_groups))]
+
     def get_all_header_values(self, dim: int, header_idx: int) -> list[str]:
         return [
             header["attributeHeader"]["labelValue"]
@@ -148,6 +153,10 @@ def exec_def(self) -> ExecutionDefinition:
     def result_id(self) -> str:
         return self._r["links"]["executionResult"]
 
+    @property
+    def dimensions(self) -> Any:
+        return self._r["dimensions"]
+
     def read_result(self, limit: Union[int, list[int]], offset: Union[None, int, list[int]] = None) -> ExecutionResult:
         """
         Reads from the execution result.