Fix downloading multiple packages of the same NEVRA test

By default re.search() (used by "stdout does not contain") does not
match across multiple lines. To bypass this limitation and check that
the package name is not present on multiple lines, use "(.|\n)*" pattern
instead of ".*".

Before this patch, the step didn't actually test anything and would
always pass.

dnf-behave-tests/dnf/plugins-core/download-binary.feature

@@ -114,9 +114,12 @@ Scenario: Download an existing RPM when there are multiple packages of the same
     And stdout contains "filesystem-3.9-2.fc29.x86_64.rpm"
     And stdout contains "wget-1.19.5-5.fc29.x86_64.rpm"
       # check that each file was being downloaded only once
-    And stdout does not contain "setup.*setup"
-    And stdout does not contain "filesystem.*filesystem"
-    And stdout does not contain "wget.*wget"
+      # By default re.search() (used by "stdout does not contain") does not match
+      # across multiple lines. To bypass this limitation and check that the package
+      # name is not present on multiple lines, use "(.|\n)*" pattern instead of ".*".
+    And stdout does not contain "setup(.|\n)*setup"
+    And stdout does not contain "filesystem(.|\n)*filesystem"
+    And stdout does not contain "wget(.|\n)*wget"
       # check that the files have been downloaded
     And file "/tmp/download/setup-2.12.1-1.fc29.noarch.rpm" exists
     And file "/tmp/download/filesystem-3.9-2.fc29.x86_64.rpm" exists