Fix DeprecationWarning / SyntaxWarning in regex

[Artalus]

Starting with Python 3.12, Conan verbosely complains about deprecated syntax in patch_ng:

$ conan
/tmp/conan2/.venv/lib/python3.12/site-packages/patch_ng.py:427: SyntaxWarning: invalid escape sequence '\d'
  re_hunk_start = re.compile(b"^@@ -(\d+)(,(\d+))? \+(\d+)(,(\d+))? @@")
/tmp/conan2/.venv/lib/python3.12/site-packages/patch_ng.py:578: SyntaxWarning: invalid escape sequence '\s'
  re_filename_date_time = b"^--- ([^\t]+)(?:\s([0-9-]+)\s([0-9:]+)|.*)"
/tmp/conan2/.venv/lib/python3.12/site-packages/patch_ng.py:621: SyntaxWarning: invalid escape sequence '\+'
  re_filename_date_time = b"^\+\+\+ ([^\t]+)(?:\s([0-9-]+)\s([0-9:]+)|.*)"
/tmp/conan2/.venv/lib/python3.12/site-packages/patch_ng.py:653: SyntaxWarning: invalid escape sequence '\d'
  match = re.match(b"^@@ -(\d+)(,(\d+))? \+(\d+)(,(\d+))? @@(.*)", line)

Consumer commands
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What was DeprecationWarning in older Pythons (see #22) is now a SyntaxWarning - which is probably why they now appear in Conan output.

This was fixed in upstream in the PR merged after this fork was created: techtonik#72

Closes #22

Closes #10

[uilianries]

Hello @Artalus !! Thank you for pushing this hotfix! We gonna merge the PR #30 first, so we can run the CI again and validate your PR. At first sight it looks totally fine.

[uilianries]

LGTM. It matches the upstream PR and using r is much safer for regex.

[uilianries]

@Artalus your PR is merged, thank you! We will be looking other issues along the week, before preparing a new release.