Fix error stack handling

[Srlion]

Fixes #64

Works exactly the same how it worked before, but now it won't throw an error for not being able to get the stack correctly,

New message is:

[GLuaTest]: Test run starting...

[GLuaTest] === Running goobie_sql/sqlite.lua... ===
[GLuaTest] FAIL [love or hate, you gonna eat it]
    File:
       addons/goobie_sql/lua/tests/goobie_sql/sqlite.lua

    Context:
      _____________________________________________________________
     |
  17 | do return {
  18 |     cases = {
  19 |         {
  20 |             name = "love or hate, you gonna eat it",
  21 |             func = function()
  22 |                 ("s"):gsub("s", function() <- Unhandled
     |_____________________________________________________________



[GLuaTest] Test run complete! 🎉
[GLuaTest] Ran 1 tests from 1 test groups in 0.008 seconds
[GLuaTest] | PASS: 0
[GLuaTest] | FAIL: 1
[GLuaTest] | EMPT: 0
[GLuaTest] | SKIP: 0

Test failures:
=== goobie_sql/sqlite.lua ===
FAIL [love or hate, you gonna eat it]


[GLuaTest]: Test run complete!

[Srlion]

Now it's in a good state, almost all error cases are handled. When a "case" function does something like this:

{
            name = "FetchOneSuccessAsync",
            func = function()
                return error("no!!")
            end
        },

There is no stack to get to tell where the error raised from, so we just point to the case's function:

Failed to get a stack, probably returning a function that errored! For example, 'return error('!')'
[GLuaTest] FAIL [FetchOneSuccessAsync]
    File:
       addons/goobie_sql/lua/tests/goobie_sql/fetchone.lua

    Context:
      _______________________________________________
     |
  29 |
  30 | cases = {
  31 |
  32 |     {
  33 |         name = "FetchOneSuccessAsync",
  34 |         func = function() <- Unhandled
     |_______________________________________________

if the case function changes to non tail call and errors

{
            name = "FetchOneSuccessAsync",
            func = function()
               error("no!!")
            end
        },

[GLuaTest] FAIL [FetchOneSuccessAsync]
    File:
       addons/goobie_sql/lua/tests/goobie_sql/fetchone.lua

    Locals:
       yes = true

    Context:
      _________________________________________________
     |
  31 |
  32 | {
  33 |     name = "FetchOneSuccessAsync",
  34 |     func = function()
  35 |         local yes = true
  36 |         error("no!!") <- Unhandled: no!!
     |_________________________________________________