Improve file/line attribution for macros

[timholy]

This makes it easier to identify the caller of a macro.
This fixes a test failure on nightly.

xref #498

[codecov]

Codecov Report

Merging #500 (48ad4db) into master (398721d) will decrease coverage by 0.78%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #500      +/-   ##
==========================================
- Coverage   86.91%   86.13%   -0.79%     
==========================================
  Files          12       12              
  Lines        2362     2394      +32     
==========================================
+ Hits         2053     2062       +9     
- Misses        309      332      +23     

Impacted Files	Coverage Δ
src/utils.jl	86.02% <100.00%> (-0.73%)	⬇️
src/interpret.jl	83.41% <0.00%> (-3.20%)	⬇️
src/types.jl	73.68% <0.00%> (-0.65%)	⬇️
src/breakpoints.jl	94.85% <0.00%> (-0.52%)	⬇️
src/optimize.jl	97.39% <0.00%> (-0.31%)	⬇️
src/commands.jl	93.06% <0.00%> (+0.08%)	⬆️
src/construct.jl	91.07% <0.00%> (+0.11%)	⬆️

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[aviatesk]

Hm, but this PR seems to cause a failure in v1.0 CI. I'd like to drop the support anyway, so I'm just fine to merge this as is.

[timholy]

In this case, this change ended up fixing a failure on older Julia versions, and we were effectively doing a @test_broken. Nice when it works out that way.