LayerFromReader: buffer contents to a temp file instead of in memory

[imjasonh]

See https://twitter.com/ariadneconill/status/1491913976795602947

Also mark the method as Deprecated, and reimplement our own only usage of it in pkg/crane.Layer(filemap) using tarball.LayerFromOpener instead.

[codecov-commenter]

Codecov Report

Merging #1285 (5f2a418) into main (a44adc3) will decrease coverage by 0.02%.
The diff coverage is 25.00%.

@@            Coverage Diff             @@
##             main    #1285      +/-   ##
==========================================
- Coverage   74.01%   73.99%   -0.03%     
==========================================
  Files         112      112              
  Lines        8374     8379       +5     
==========================================
+ Hits         6198     6200       +2     
- Misses       1573     1575       +2     
- Partials      603      604       +1     

Impacted Files	Coverage Δ
pkg/v1/tarball/layer.go	68.71% <25.00%> (-0.91%)	⬇️

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