Remove undocumented djdt.init() from the exported namespace

[jdufresne]

The function is not documented and there is no reason a third party
panel would need to call init() a 2nd time.

[codecov]

Codecov Report

Merging #1287 into master will increase coverage by 0.13%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1287      +/-   ##
==========================================
+ Coverage   86.61%   86.74%   +0.13%     
==========================================
  Files          25       25              
  Lines        1449     1449              
  Branches      205      205              
==========================================
+ Hits         1255     1257       +2     
+ Misses        142      141       -1     
+ Partials       52       51       -1     

Impacted Files	Coverage Δ
debug_toolbar/panels/profiling.py	91.07% <0.00%> (+1.78%)	⬆️

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[matthiask]

djdt.init was made available for supporting TurboLinks and similar software, so there's a good reason for it being part of the public API. Or maybe there exists a better way to accomplish this but exporting init certainly works.

[matthiask]

Here's the pull request which exported djdt.init: #1180

[jdufresne]

Thanks for that link. I'll take a deeper look into that issue and try to grok it.