[pdata] Make Slice.AsRaw() method exported

[dmitryax]

Resolves #5310

[codecov]

Codecov Report

Merging #5311 (0fe06cb) into main (df00d05) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #5311      +/-   ##
==========================================
+ Coverage   90.54%   90.58%   +0.03%     
==========================================
  Files         190      190              
  Lines       11109    11109              
==========================================
+ Hits        10059    10063       +4     
+ Misses        827      824       -3     
+ Partials      223      222       -1     

Impacted Files	Coverage Δ
pdata/internal/common.go	95.38% <100.00%> (+0.76%)	⬆️

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[bogdandrutu]

What is the need for this method? Just curious.

[dmitryax]

It's needed in contrib in one place https://github.com/open-telemetry/opentelemetry-collector-contrib/blob/9c214be44477ef84daa0770a3f0464fc25eae7cf/exporter/lokiexporter/encode_json.go#L98

Also it seems inconsistent that Map has it while Slice doesn't