FORWARD PORTS NEEDED

[jkowalleck]

since v4 got in dev phase, some fixes were applied to older versions.
these need to be ported forward to the v4

[jkowalleck]

• port forward: fix: prevent errors on metadata handling for some specification versions #330

[jkowalleck]

• port forward: a solution for Serialization of nested Components with Dependencies drops transitive dependencies #328
  ala fix: serialize dependency graph for nested components #329

[jkowalleck]

• port forward: the mock of ThisTool.version in tests - test: mock ThisTool.version for constisten results #335

[jkowalleck]

• port forward: the package-relative schema paths in tests - fix(tests): make tests' schema paths relative to cyclonedx package #338

[madpah]

@jkowalleck am reviewing the items you market for forward porting to 4.0.0:

• 👍 fix: prevent errors on metadata handling for some specification versions #330 - I don't believe this directly applies to the 4.0.0 codebase.
• 👍 Serialization of nested Components with Dependencies drops transitive dependencies #328 - confirmed as already fixed in 4.0.0
• 👍 Hard-coded versions in fixtures #334 - appears to already be included in 4.0.0
• 👍 feat: include tests in sdist releases #336 (partial - PR fix(tests): make tests' schema paths relative to cyclonedx package #338) - Confirmed included in 4.0.0

[madpah]

Included in 4.0.0 - now released.