tests: vendor sRGB.icc instead of relying on distro-specific paths

This is no longer the case with ImageMagick 7.

src/img2pdf_test.py

@@ -21,17 +21,7 @@ import json
 import pathlib
 
 SCRIPT_DIR = pathlib.Path(__file__).resolve().parent
-ICC_PROFILE = None
+ICC_PROFILE = SCRIPT_DIR / "tests" / "data" / "sRGB.icc"
-ICC_PROFILE_PATHS = (
-        "/usr/share/color/icc/ghostscript/srgb.icc",
-        "/usr/share/ghostscript/9.54.0/iccprofiles/srgb.icc",
-        "/usr/share/color/icc/sRGB.icc",
-        "/usr/share/color/icc/OpenICC/sRGB.icc",
-)
-for path in ICC_PROFILE_PATHS:
-    if os.path.exists(path):
-        ICC_PROFILE = path
-        break
 
 HAVE_MUTOOL = True
 try:
@@ -317,8 +307,6 @@ def compare(im1, im2, exact, icc, cmyk):
     else:
         iccargs = []
         if icc:
-            if ICC_PROFILE is None:
-                pytest.skip("Could not locate an ICC profile")
             iccargs = ["-profile", ICC_PROFILE]
         psnr = subprocess.run(
             ["compare"]
@@ -432,8 +420,6 @@ def compare_pdfimages_png(tmpdir, img, pdf, exact=True, icc=False):
         )
     else:
         if icc:
-            if ICC_PROFILE is None:
-                pytest.skip("Could not locate an ICC profile")
             psnr = subprocess.run(
                 [
                     "compare",