[core] Duplicate validation errors

[aalmiray]

Task List

• Steps to reproduce provided
• Stacktrace (if present) provided
• Example that reproduces the problem (link to git repository is ideal)
• Full description of the issue provided (see below)

Steps to Reproduce

1. Configure a project with JReleaser
2. Do not configure a project version.
3. Do not set JRELEASER_PROJECT_VERSION.
4. Invoke the config command.

Expected Behaviour

A single error should appear

[ERROR] == JReleaser ==
[ERROR] project.version must not be blank. Configure a value using the CLI yaml DSL, or define a JRELEASER_PROJECT_VERSION environment variable, or define a key/value pair in /Users/duke/.jreleaser/config.toml
JReleaser has not been properly configured.

Actual Behaviour

Duplicate errors appear

[ERROR] == JReleaser ==
[ERROR] project.version must not be blank. Configure a value using the CLI yaml DSL, or define a JRELEASER_PROJECT_VERSION environment variable, or define a key/value pair in /Users/duke/.jreleaser/config.toml
[ERROR] project.version must not be blank. Configure a value using the CLI yaml DSL, or define a JRELEASER_PROJECT_VERSION environment variable, or define a key/value pair in /Users/duke/.jreleaser/config.toml
JReleaser has not been properly configured.

Environment Information

• Operating System: N/A
• JReleaser Version: 0.5.0
• JDK Version: N/A