docs: fix 5 typos in comments and log messages

[Avicennasis]

Summary

Fix 5 typos across 5 files - four in log/comment text and one in a label description.

• utility/service.js (L169): cancelPipeline() logged "Error while fetching pipeline variable", copy-pasted from getPipelineVariables() eleven lines above -> "Error while canceling pipeline". The genuine occurrence at L158 inside getPipelineVariables() is left as-is.
• veracode-issues/pipelineScanIssue.js (L29): comment with the fist of (possible) multiple flaws -> first
• veracode-scans/policy-scan/sandbox.js (L21): log Error while retriving application details -> retrieving
• veracode-scans/policy-scan/remove-sandbox.js (L18): log remove sandbox scan failed becasue sourceBranch not found -> because
• utility/labels.js (L35): label description 'A Veracode Flaw,Unknown severity' was missing the space after the comma. The other six severity entries in the same object all read 'A Veracode Flaw, <X> severity'.

Notes for reviewers

• The service.js change is the only one that alters a message a user might grep for. It is a console.log in a catch block; nothing in the repository asserts on the string, and the copy-paste made the cancel path report a misleading error.
• labels.js description is only sent when a label is created; checkLabelExists matches on name, so the added space does not affect label lookup.
• No identifiers were renamed and no logic was changed.
• retriving also appears in veracode-scans/policy-scan/policy.js (L139, L141) and utility/common.js (L79). Those were outside the scope of this pass and are left untouched - happy to fold them in if you would prefer a single sweep.
• Heads-up on licensing: the repository has no LICENSE file. package.json declares "license": "ISC", but alongside an empty "description" and "author" that reads more like an unedited npm init default than a deliberate grant. There is no explicit licence covering outside contributions. We noticed and wanted to flag it rather than assume - adding a LICENSE file would make things clearer for future contributors.

No functional changes - comments, log messages and one label description only.