feat(registry-lint): use jv instead of ajv for clear error output

[icefed]

If package.yaml is not valid, registry-lint always got error: Unexpected identifier, the output can be clear.

use https://github.com/santhosh-tekuri/jsonschema jv tool.

ex: invalid source type

$ jv -d 7 package.schema.json package.yaml
schema package.schema.json: ok

instance package.yaml: failed
jsonschema validation failed with 'file:///Users/Tom/Downloads/package.schema.json#'
- at '/source': allOf failed
  - at '/source': oneOf failed, none matched
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:cargo/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:composer/.+/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:gem/.+@.+'
    - at '/source': oneOf failed, none matched
      - at '/source': validation failed
        - at '/source': missing property 'download'
        - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:generic/.+@.+'
      - at '/source': validation failed
        - at '/source': missing property 'build'
        - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:generic/.+@.+'
    - at '/source': oneOf failed, none matched
      - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:github/.+/.+@.+'
      - at '/source': validation failed
        - at '/source': missing property 'build'
        - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:github/.+/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:golang/.+/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:luarocks/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:npm/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:nuget/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:opam/.+@.+'
    - at '/source': validation failed
      - at '/source': missing property 'download'
      - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:openvsx/.+/.+@.+'
    - at '/source/id': 'pkg:github.com/bufbuild/[email protected]' does not match pattern '^pkg:pypi/.+@.+'