Provide meaningful error message for bom and vex exceeding Jackson's character limit

[nscuro]

Description

Provides a meaningful error message for bom and vex exceeding Jackson's character limit.

Also document the limitation in the OpenAPI spec of the respective PUT methods that accept JSON payloads.

Addressed Issue

Fixes #3182

Additional Details

Example response for the PUT /api/v1/bom endpoint:

{
  "status": 400,
  "title": "The provided JSON payload could not be mapped",
  "detail": "The BOM is too large to be transmitted safely via Base64 encoded JSON value. Please use the \"POST /api/v1/bom\" endpoint with Content-Type \"multipart/form-data\" instead. Original cause: String length (20000001) exceeds the maximum length (20000000) (through reference chain: org.dependencytrack.resources.v1.vo.BomSubmitRequest[\"bom\"])"
}

Checklist

• I have read and understand the contributing guidelines
• This PR fixes a defect, and I have provided tests to verify that the fix is effective
• This PR implements an enhancement, and I have provided tests to verify that it works as intended
• This PR introduces changes to the database model, and I have added corresponding update logic
• This PR introduces new or alters existing behavior, and I have updated the documentation accordingly

[codacy-production]

Coverage summary from Codacy

See diff coverage on Codacy

Coverage variation	Diff coverage
✅ +0.00% (target: -1.00%)	✅ 90.91% (target: 70.00%)

Coverage variation details

	Coverable lines	Covered lines	Coverage
Common ancestor commit (753924d)	21517	15938	74.07%
Head commit (a6804a4)	21539 (+22)	15955 (+17)	74.07% (+0.00%)

Coverage variation is the difference between the coverage for the head and common ancestor commits of the pull request branch: <coverage of head commit> - <coverage of common ancestor commit>

Diff coverage details

	Coverable lines	Covered lines	Diff coverage
Pull request (#3558)	22	20	90.91%

Diff coverage is the percentage of lines that are covered by tests out of the coverable lines that the pull request added or modified: <covered lines added or modified>/<coverable lines added or modified> * 100%

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