Give the sheet encoding test cases short ids

pytest puts each test id in PYTEST_CURRENT_TEST, and Windows caps an
environment variable at 32,767 characters; one case's id was 70,000.

Author: craigthackerx

CHANGELOG.md

@@ -98,6 +98,8 @@ All notable changes to libre-devops-helpers are recorded here. The project follo
 - `just use` and `just token` ran commands that had moved under `az` and `entra`.
 - Four CLI tests failed in GitHub Actions, where Typer styles and wraps usage errors; they
   now compare the message's plain text.
+- A sheet test's 70,000 character id failed on Windows, which caps an environment
+  variable (pytest's `PYTEST_CURRENT_TEST`) at 32,767 characters; its cases have short ids.
 
 ### Security
 

tests/core/test_sheets.py

@@ -182,6 +182,9 @@ def test_a_document_type_declaration_is_refused_before_parsing(tmp_path, monkeyp
         '<?xml version="1.0" encoding="utf-8"?><worksheet/>'.encode("utf-16"),
         b'<?xml version="1.0"' + b" " * 70_000 + b"?><worksheet/>",
     ],
+    # Short ids: pytest puts the id in PYTEST_CURRENT_TEST, and Windows caps a variable
+    # at 32,767 characters.
+    ids=["cp037", "utf-16 declared", "utf-16 bytes", "a long declaration"],
 )
 def test_a_part_in_another_encoding_is_refused(tmp_path, content):
     parts: dict[str, str | bytes] = dict(workbook_parts({"Plan": []}))