LDEV-3816 - fix from double slash creation for consistent file access in graph.cfm

[andreasRu]

GetTempDirectory() already echos a trailing slash. Thus, the code in graph.cfm creates file location paths with double slashes as follows: On Ubuntu 20.04 LTS: /somepath/WEB-INF/lucee/temp//graph/5A650255-8EB7-472A-86D943CE97EAD884.png On Windows 10: C:\somepath\WEB-INF\lucee\temp\/graph/E1F8959F-B1F9-4845-8052502D385FEDF7.png

This PR removes the preceeding slash for better file path consistency.

Please see also: https://dev.lucee.org/t/error-graph-cfm/9483

[andreasRu]

https://luceeserver.atlassian.net/browse/LDEV-3816

[michaeloffner]

already implemented

[michaeloffner]

@andreasRu thanks for your input