CSV Idiomatic Errors

[cpheps]

• Changed errors in CSV parser operator to have lowercase first words to be idiomatic.
• Removed some fmt.Errorf in favor of errors.New where formatting wasn't needed to create error

[linux-foundation-easycla]

The committers are authorized under a signed CLA.

• ✅ Corbin Phelps (274546b, 560c9fc)

[jsirianni]

@cpheps Let me know when CLA is handled and I will trigger CI 👍

[cpheps]

@jsirianni will do. @djaglowski is working on getting me signed up I'll follow up with you when that's done.

[djaglowski]

LGTM, but waiting on EasyCLA approval

[codecov]

Codecov Report

Merging #323 (560c9fc) into main (d86516e) will decrease coverage by 0.1%.
The diff coverage is 100.0%.

@@           Coverage Diff           @@
##            main    #323     +/-   ##
=======================================
- Coverage   77.0%   76.9%   -0.2%     
=======================================
  Files         94      94             
  Lines       4410    4410             
=======================================
- Hits        3400    3395      -5     
- Misses       695     698      +3     
- Partials     315     317      +2     

Impacted Files	Coverage Δ
operator/builtin/parser/csv/csv.go	97.3% <100.0%> (ø)
operator/builtin/input/file/file.go	72.3% <0.0%> (-1.9%)	⬇️
operator/builtin/input/tcp/tcp.go	78.0% <0.0%> (-1.7%)	⬇️