Move "count" global to test global struct

[jphickey]

Describe the bug
Should not have random global variables around, particularly variables with simple/common names, as it may silently overwrite an existing variable (i.e. if any other app/lib makes a global called "count" some OS's will just happily bind to the existing variable, not make a separate instance, when dynamic refs are resolved after loading).

cFE/modules/cfe_testcase/src/es_task_test.c

Line 36 in cc8c9a1

uint32 count = 0;

Expected behavior
Now that we have a proper global struct, CFE_FT_Global_t - This should be moved into it.

Reporter Info
Joseph Hickey, Vantage Systems, Inc.