counters: add screenshots dir of counters.ui.swtbot tests to .gitignore

Change-Id: Ia29a94e8b19edf6017c96e5d3af65624b2de01e4
Signed-off-by: Bernd Hufmann <Bernd.Hufmann@ericsson.com>
Reviewed-on: https://git.eclipse.org/r/157737
Tested-by: Trace Compass Bot <tracecompass-bot@eclipse.org>
Reviewed-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
Tested-by: Matthew Khouzam <matthew.khouzam@ericsson.com>
diff --git a/analysis/org.eclipse.tracecompass.analysis.counters.ui.swtbot.tests/.gitignore b/analysis/org.eclipse.tracecompass.analysis.counters.ui.swtbot.tests/.gitignore
new file mode 100644
index 0000000..750e145
--- /dev/null
+++ b/analysis/org.eclipse.tracecompass.analysis.counters.ui.swtbot.tests/.gitignore
@@ -0,0 +1 @@
+screenshots/