Add test that validates fingerprint.StartsWith

[jsirianni]

Description of Changes

Same as open-telemetry/opentelemetry-log-collection#145

Please check that the PR fulfills these requirements

• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)
• Add a changelog entry (for non-trivial bug fixes / features)
• CI passes

[djaglowski]

Log Files	Logs / Second	CPU Avg (%)	CPU Avg Δ (%)	Memory Avg (MB)	Memory Avg Δ (MB)
1	1000	1.4138083	+0.13790584	128.63052	+0.004180908
1	5000	4.9655886	+0.37934923	137.38914	+1.8741913
1	10000	11.414107	+1.5862837	144.52249	+0.55145264
1	50000	54.80313	+5.66481	174.2504	-0.16770935
1	100000	87.845474	-7.4488373	222.01064	-18.012802
10	100	1.9655142	+0.20687366	134.13672	+0.09927368
10	500	5.5864544	-1.1551642	139.46565	+0.4035492
10	1000	10.620748	-0.034568787	143.33769	-5.137253
10	5000	50.50157	-3.1547813	176.41164	+2.1430511
10	10000	104.86178	+2.6952972	227.08432	+9.212692

[codecov]

Codecov Report

Merging #318 (ce38677) into master (80f21a1) will increase coverage by 0.03%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #318      +/-   ##
==========================================
+ Coverage   70.21%   70.24%   +0.03%     
==========================================
  Files         119      119              
  Lines        6330     6330              
==========================================
+ Hits         4444     4446       +2     
+ Misses       1421     1419       -2     
  Partials      465      465              

Impacted Files	Coverage Δ
operator/builtin/input/file/fingerprint.go	88.24% <ø> (ø)
operator/builtin/output/otlp/otlp.go	62.96% <0.00%> (-2.47%)	⬇️
operator/builtin/input/file/file.go	78.77% <0.00%> (+2.74%)	⬆️

---

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[djaglowski]

Log Files	Logs / Second	CPU Avg (%)	CPU Avg Δ (%)	Memory Avg (MB)	Memory Avg Δ (MB)
1	1000	1.4482837	+0.17238116	127.57732	-1.0490265
1	5000	5.069172	+0.48293257	136.94922	+1.4342651
1	10000	10.328119	+0.50029564	143.96915	-0.0018920898
1	50000	51.411953	+2.273632	180.12244	+5.7043304
1	100000	96.50711	+1.2127991	238.6207	-1.4027405
10	100	1.931063	+0.17242253	133.90787	-0.12957764
10	500	5.586325	-1.1552935	137.43817	-1.6239319
10	1000	10.724245	+0.06892872	143.40598	-5.0689697
10	5000	54.442932	+0.78657913	176.86314	+2.5945587
10	10000	98.967354	-3.1991272	225.20824	+7.336609