When viewing graph debug from remote data collector, File Not Found warnings can appear incorrectly

[cigamit]

Describe the bug
When viewing a graph in debug mode enabled on remote data collectors, instead of seeing an 'Ok' or some warning as to why the RRDtool did not render, you get a 'File not found' warning as if the syntax is not leveraging the remote_agent.php file.

To Reproduce
Steps to reproduce the behavior:

1. Login to a Remote Data Collector in 'online' mode.
2. Goto Console > Management > Graphs and Edit a Graph
3. Enable Graph Debug
4. See error

Expected behavior
You should get rendering data from the Remote Agent.

[cigamit]

For now, we will simply skip the check.

[bmfmancini]

Confirmed working fix 1.2.7 off the 1.2.x branch