Verify tracy nil checks

[sprunk]

The if tracy then tracy.foo() end pattern exists in a bunch of places, e.g.

Beyond-All-Reason/common/luaUtilities/json.lua

Line 534 in a68ac13

if tracy then tracy.ZoneBeginN("Json:Decode") end

But if tracy is disabled then the tracy.foo() is removed from code, so the if tracy check is redundant and just incurs a perf cost whether Tracy is present or not. Remove those checks.