Windows drive-relative pathlib.Path.resolve(strict=False) resolves incorrectly in pyfakefs 6.2.0

Describe the bug

On Windows, pathlib.Path.resolve(strict=False) resolves drive-relative paths incorrectly when pyfakefs is active.

A Windows path like c:test\test_data\dummy1.xml is drive-relative, not absolute. With the current directory set to C:\test, CPython's real pathlib resolves it to:

C:\test\test\test_data\dummy1.xml

With pyfakefs 6.2.0 active, the same path resolves to:

c:\est\test_data\dummy1.xml

The first character of the relative path component (t in test) appears to be dropped, and the path is treated like it starts at the drive root.

This looks like a regression from pyfakefs 6.1.4 to 6.2.0. The same test passed with pyfakefs 6.1.4 and fails with pyfakefs 6.2.0.

How To Reproduce

Please run this on Windows:

from pathlib import Path
import os

from pyfakefs.fake_filesystem_unittest import Patcher


with Patcher() as patcher:
    fs = patcher.fs
    root = Path("/test")
    fs.create_file(root / "test_data" / "dummy1.xml")
    os.chdir(root)

    drive = Path.cwd().drive
    path = Path(f"{drive.lower()}test\\test_data/dummy1.xml")
    resolved = path.resolve(strict=False)

    print("cwd:", Path.cwd())
    print("path:", path)
    print("resolved:", resolved)

    assert str(resolved) == r"C:\test\test\test_data\dummy1.xml"

Actual output with pyfakefs 6.2.0:

cwd: C:\test
path: c:test\test_data\dummy1.xml
resolved: c:\est\test_data\dummy1.xml

Expected output:

cwd: C:\test
path: c:test\test_data\dummy1.xml
resolved: C:\test\test\test_data\dummy1.xml

For comparison, outside pyfakefs, Path.resolve(strict=False) resolves the drive-relative path relative to the current directory on that drive as expected.

Your environment

Output from the affected environment:

platform: Windows
Python: 3.12.12
pyfakefs: 6.2.0
pytest: 9.0.3

Start with the provided Patcher reproduction on Windows and compare pathlib.Path.resolve(strict=False) under pyfakefs 6.2.0 with CPython outside pyfakefs. Done means the drive-relative path resolves to C:\test\test\test_data\dummy1.xml without dropping the first character.