Allow for concurrent layer reads

[wagoodman]

Note: uses unmerged changes from go-sync (using go.work locally)

[github-actions]

Benchmark Test Results

Benchmark results from the latest changes vs base branch

make .tool/task
make[1]: Entering directory '/home/runner/work/stereoscope/stereoscope'
make[1]: Leaving directory '/home/runner/work/stereoscope/stereoscope'
.tool/task show-benchstat
FAIL	github.com/anchore/stereoscope [build failed]
FAIL	github.com/anchore/stereoscope/examples [build failed]
PASS
ok  	github.com/anchore/stereoscope/internal	0.003s
?   	github.com/anchore/stereoscope/internal/bus	[no test files]
PASS
ok  	github.com/anchore/stereoscope/internal/containerd	0.008s
PASS
ok  	github.com/anchore/stereoscope/internal/docker	0.005s
?   	github.com/anchore/stereoscope/internal/log	[no test files]
PASS
ok  	github.com/anchore/stereoscope/internal/podman	0.005s
?   	github.com/anchore/stereoscope/pkg/event	[no test files]
FAIL	github.com/anchore/stereoscope/pkg/event/parsers [build failed]
goos: linux
goarch: amd64
pkg: github.com/anchore/stereoscope/pkg/file
cpu: AMD EPYC 7763 64-Core Processor                
BenchmarkTarIndex-4   	   35018	     34370 ns/op	    5701 B/op	      93 allocs/op
BenchmarkTarIndex-4   	   34812	     34415 ns/op	    5700 B/op	      93 allocs/op
BenchmarkTarIndex-4   	   34477	     34383 ns/op	    5702 B/op	      93 allocs/op
BenchmarkTarIndex-4   	   34929	     34557 ns/op	    5700 B/op	      93 allocs/op
BenchmarkTarIndex-4   	   34560	     34359 ns/op	    5702 B/op	      93 allocs/op
BenchmarkTarIndex-4   	   34912	     34462 ns/op	    5702 B/op	      93 allocs/op
BenchmarkTarIndex-4   	   34845	     35105 ns/op	    5700 B/op	      93 allocs/op
PASS
ok  	github.com/anchore/stereoscope/pkg/file	10.868s
PASS
ok  	github.com/anchore/stereoscope/pkg/filetree	0.005s
?   	github.com/anchore/stereoscope/pkg/filetree/filenode	[no test files]
FAIL	github.com/anchore/stereoscope/pkg/image [build failed]
FAIL	github.com/anchore/stereoscope/pkg/image/containerd [build failed]
FAIL	github.com/anchore/stereoscope/pkg/image/docker [build failed]
FAIL	github.com/anchore/stereoscope/pkg/image/oci [build failed]
FAIL	github.com/anchore/stereoscope/pkg/image/oci/credhelpers [build failed]
FAIL	github.com/anchore/stereoscope/pkg/image/podman [build failed]
FAIL	github.com/anchore/stereoscope/pkg/image/sif [build failed]
FAIL	github.com/anchore/stereoscope/pkg/imagetest [build failed]
PASS
ok  	github.com/anchore/stereoscope/pkg/tree	0.004s
PASS
ok  	github.com/anchore/stereoscope/pkg/tree/node	0.003s
FAIL	github.com/anchore/stereoscope/test/integration [build failed]
FAIL	github.com/anchore/stereoscope/test/integration/test-fixtures/registry [build failed]
FAIL
goos: linux
goarch: amd64
pkg: github.com/anchore/stereoscope/pkg/file
cpu: AMD EPYC 7763 64-Core Processor                
           │ .tmp/benchmark-bbfe66a.txt │
           │           sec/op           │
TarIndex-4                  34.42µ ± 2%

           │ .tmp/benchmark-bbfe66a.txt │
           │            B/op            │
TarIndex-4                 5.567Ki ± 0%

           │ .tmp/benchmark-bbfe66a.txt │
           │         allocs/op          │
TarIndex-4                   93.00 ± 0%
goos: linux
goarch: amd64
pkg: github.com/anchore/stereoscope/pkg/file
cpu: AMD EPYC 7763 64-Core Processor                
           │ .tmp/benchmark-bbfe66a.txt │
           │           sec/op           │
TarIndex-4                  34.42µ ± 2%

           │ .tmp/benchmark-bbfe66a.txt │
           │            B/op            │
TarIndex-4                 5.567Ki ± 0%

           │ .tmp/benchmark-bbfe66a.txt │
           │         allocs/op          │
TarIndex-4                   93.00 ± 0%