chore(source): standardize sources with merge endpionts and deduplication

[ivankatliarchuk]

What does it do ?

• MergeEndpoint method sorting and deduplicate targets
• All sources to utilize merge endpoints method, as there is very little reason to push duplication upstream to plan/provider

Motivation

• Standarise sources output

Relates #6192

More

• Yes, this PR title follows Conventional Commits
• Yes, I added unit tests
• Yes, I updated end user documentation accordingly

┌──────────┬───────┐
│ Category │ Lines │
├──────────┼───────┤
│ Non-test │ +52   │
├──────────┼───────┤
│ Test     │ +119  │
├──────────┼───────┤
│ Ratio    │ 1:2.2│
└──────────┴───────┘

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[coveralls]

Pull Request Test Coverage Report for Build 21795351288

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 303 unchanged lines in 12 files lost coverage.
• Overall coverage decreased (-0.02%) to 79.142%

---

Files with Coverage Reduction	New Missed Lines	%
utils.go	2	97.1%
openshift_route.go	10	84.38%
endpoint.go	11	85.76%
istio_gateway.go	12	87.5%
f5_virtualserver.go	14	78.13%
contour_httpproxy.go	14	82.96%
ingress.go	15	88.3%
ambassador_host.go	15	82.64%
skipper_routegroup.go	28	37.97%
istio_virtualservice.go	29	86.74%

Totals
Change from base Build 21559764040:	-0.02%
Covered Lines:	16027
Relevant Lines:	20251

---

💛 - Coveralls