Remove invalid escape sequences

This emits a warning on Python 3.8. Let's just fix it.

Signed-off-by: Lubomír Sedlář <lsedlar@redhat.com>

pungi/phases/pkgset/sources/source_koji.py

@@ -86,7 +86,7 @@ def variant_dict_from_str(compose, module_str):
         module_info = {}
         # The regex is matching a string which should represent the release number
         # of a module. The release number is in format: "%Y%m%d%H%M%S"
-        release_regex = re.compile("^(\d){14}$")
+        release_regex = re.compile(r"^(\d){14}$")
 
         section_start = module_str.rfind('-')
         module_str_first_part = module_str[section_start+1:]

tests/test_extra_files_phase.py

@@ -159,7 +159,9 @@ class TestCopyFiles(helpers.PungiTestCase):
             extra_files.copy_extra_files(
                 compose, [cfg], 'x86_64', compose.variants['Server'], package_sets)
 
-        self.assertRegexpMatches(str(ctx.exception), 'No.*package.*matching bad-server\*.*')
+        self.assertRegexpMatches(
+            str(ctx.exception), r'No.*package.*matching bad-server\*.*'
+        )
 
         self.assertEqual(len(get_file_from_scm.call_args_list), 0)
         self.assertEqual(get_dir_from_scm.call_args_list, [])

tests/test_pkgset_source_koji.py

@@ -465,7 +465,7 @@ class TestCorrectNVR(helpers.PungiTestCase):
         self.compose = helpers.DummyCompose(self.topdir, {})
         self.nv = "base-runtime-f26"
         self.nvr = "base-runtime-f26-20170502134116"
-        self.release_regex = re.compile("^(\d){14}$")
+        self.release_regex = re.compile(r"^(\d){14}$")
         self.new_nv = "base-runtime:f26"
         self.new_nvr = "base-runtime:f26:20170502134116"
         self.new_nvrc = "base-runtime:f26:20170502134116:0123abcd"