CMake fixes

[Ninja3047]

• move doctest to cxx-common: lifting-bits/cxx-common#964 and remove submodule from repo
• update git_watcher.cmake to fix some bugs, most notably changing CMAKE_BINARY_DIR to CMAKE_CURRENT_BINARY_DIR
• remove llvm.cmake and janky find_llvm, use upstream llvm recommended cmake incantation
• update FindZ3.cmake to fix some bugs, most notably changing CMAKE_SOURCE_DIR a temporary path

[Ninja3047]

won't build until lifting-bits/cxx-common#964 gets merged and tagged so do not merge until then

[github-actions[bot]]

See the diff generated by this PR for the tests here: https://github.com/lifting-bits/rellic/actions/runs/2950063358

### fizzbuzz.bc ```diff ``` ### typedefs_of_typedefs.bc ```diff ``` ### switch_loop.bc ```diff ``` ### func_cond_zero_arg.bc ```diff ``` ### fcmp.bc ```diff ``` ### conflicting_names.bc ```diff ``` ### struct.bc ```diff ``` ### issue_183_literal_structs.bc ```diff ``` ### zeroinit.bc ```diff ``` ### issue_127_uint128_t_lit.bc ```diff ``` ### struct_swap.bc ```diff ``` ### init_list.bc ```diff ``` ### ret0.bc ```diff ``` ### bool.bc ```diff ``` ### short.bc ```diff ``` ### cast.bc ```diff ``` ### nullptr.bc ```diff ``` ### nested_struct.bc ```diff ``` ### array_swap.bc ```diff ``` ### binops.bc ```diff ``` ### bitmask.bc ```diff ``` ### loop.bc ```diff ``` ### float.bc ```diff ``` ### reg_test_structure_fields.bc ```diff ``` ### vectors.bc ```diff ``` ### funcptr.bc ```diff ``` ### goto_loop.bc ```diff ``` ### branch.bc ```diff ``` ### bitops.bc ```diff ``` ### trunc.bc ```diff ``` ### inttoptr.bc ```diff ``` ### issue_4.bc ```diff ``` ### issue_123_uint128_t.bc ```diff ``` ### fizzbuzz_stateful.bc ```diff ``` ### issue_94_strncmp.bc ```diff ``` ### global_using_function_decl.bc ```diff ``` ### byval_struct.bc ```diff ``` ### nested_while.bc ```diff --- /dev/fd/63 2022-08-29 16:33:47.666364756 +0000 +++ /dev/fd/62 2022-08-29 16:33:47.666364756 +0000 @@ -18,14 +18,14 @@ printf("loop1 x: %d\n", var1); } } - if ((int)var1 >= 20 || (int)var1 <= 10) { + if ((int)var1 <= 10 || (int)var1 >= 20) { while ((int)var1 < 20) { var1 = var1 + 1U; printf("loop2 x: %d\n", var1); } } - if (((int)var1 >= 20 || (int)var1 <= 10) && (int)var1 >= 20) { + if (((int)var1 <= 10 || (int)var1 >= 20) && (int)var1 >= 20) { return var0; } } ``` ### func_cond_two_arg.bc ```diff ``` ### conflicting_global.bc ```diff ``` ### assert.bc ```diff ``` ### zext.bc ```diff ``` ### switch.bc ```diff ``` ### template_parameter_pack.bc ```diff ``` ### byval_tail_nogep.ll ```diff ``` ### byval_tail_gep.ll ```diff ```