fix cmdline sum command and and test

[gyorb]

Resolves #1004

[csordasmarton]

LGTM!

However, I found some issues which can be fixed very quickly.

• The sum command doesn't uniqueing the reports.
  Resolution: set isUnique attribute to True in both places:
  

  codechecker/libcodechecker/cmd/cmd_line_client.py

  Line 409 in a3d8f81

  report_filter = ttypes.ReportFilter()

report_filter.isUnique = True

codechecker/libcodechecker/cmd/cmd_line_client.py

Line 429 in a3d8f81

all_checkers_report_filter = ttypes.ReportFilter()

all_checkers_report_filter.isUnique = True

• In check_run_names function we should create a run filter which queries runs by check_names parameter:
  

  codechecker/libcodechecker/cmd/cmd_line_client.py

  Line 44 in a3d8f81

  run_info = {run.name: run for run in client.getRunData(None)}

run_filter = ttypes.RunFilter()
if check_names is not None:
    run_filter.names = check_names
    run_filter.exactMatch = True

run_info = {run.name: run for run in client.getRunData(run_filter)}

These bugs can be fixed in this pull request, or we can create another issue to fix it.

[gyorb]

I would keep this pull request for the bug fix only and create separate issues for the modifications you suggested @csordasmarton .

[csordasmarton]

Okay, I created separate issues for these problems: #1025, #1026.