Make activate set not mess with LOAD_PATH

[oxinabox]

Should fix #19 .
Does fix it for me.

@nickrobinson251 do you want to take a look and see if it fixes?
This is the branch for julia 1.7, it will need porting to other banches after it is approved

A very nice side bonus of this approach is that Pkg.activate("originalpath") actually does indeed remove the test enviroment.

[codecov-commenter]

Codecov Report

Merging #20 (c6b5d70) into release-1.7 (8d8c90c) will decrease coverage by 0.84%.
The diff coverage is 100.00%.

@@               Coverage Diff               @@
##           release-1.7      #20      +/-   ##
===============================================
- Coverage        82.02%   81.17%   -0.85%     
===============================================
  Files                3        3              
  Lines               89       85       -4     
===============================================
- Hits                73       69       -4     
  Misses              16       16              

Impacted Files	Coverage Δ
src/activate_set.jl	78.04% <100.00%> (-1.96%)	⬇️

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[nickrobinson251]

nickrobinson251 do you want to take a look and see if it fixes?
This is the branch for julia 1.7, ...

Downloaded v1.7.0-beta3.0 just for this... what is this magic?! 😆

julia> using TestEnv
 │ Package TestEnv not found, but a package named TestEnv is available from a registry.
 │ Install package?
 │   (@v1.7) pkg> add TestEnv
 └ (y/n) [y]:

[nickrobinson251]

yes, this fixes the issue for me too 😀

[nickrobinson251]

(btw, this fixes the issue i actually opened, it doesn't get all the way to ReTest.jl working with TestEnv, i'll open a new issue... i think it's a ReTest issue anyway)

edit: looks unrelated to TestEnv in fact (JuliaTesting/ReTest.jl#29)