Update most docstring code output with current Polars formatting.

Update most docstring code output with current Polars formatting:
  - doctest output checking was disabled in the past as Polars
    output/formatting was still changing a lot (like float printing).
  - Almost all doctest pass now without need to silence the output.
  - Some code examples were incomplete or wrong.
  - There are stil a few failing docstrings mostly related to time series.
  - Soon run_doc_examples.py can be run again with:
    `IGNORE_RESULT_ALL = False`

py-polars/polars/cfg.py

@@ -80,6 +80,18 @@ def set_tbl_cols(cls, n: int) -> type[Config]:
         ╞═════╪═════╪═════╪═════╪═════╪═════╡
         │ 0   ┆ 1   ┆ 2   ┆ ... ┆ 98  ┆ 99  │
         └─────┴─────┴─────┴─────┴─────┴─────┘
+
+        >>> pl.cfg.Config.set_tbl_cols(10)
+        >>> df
+        shape: (1, 100)
+        ┌─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┬─────┐
+        │ 0   ┆ 1   ┆ 2   ┆ 3   ┆ 4   ┆ ... ┆ 95  ┆ 96  ┆ 97  ┆ 98  ┆ 99  │
+        │ --- ┆ --- ┆ --- ┆ --- ┆ --- ┆     ┆ --- ┆ --- ┆ --- ┆ --- ┆ --- │
+        │ i64 ┆ i64 ┆ i64 ┆ i64 ┆ i64 ┆     ┆ i64 ┆ i64 ┆ i64 ┆ i64 ┆ i64 │
+        ╞═════╪═════╪═════╪═════╪═════╪═════╪═════╪═════╪═════╪═════╪═════╡
+        │ 0   ┆ 1   ┆ 2   ┆ 3   ┆ 4   ┆ ... ┆ 95  ┆ 96  ┆ 97  ┆ 98  ┆ 99  │
+        └─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┴─────┘
+
         """
 
         os.environ["POLARS_FMT_MAX_COLS"] = str(n)