feat(project): Offer configPath property to workspace configs (workspace/1.1)

[maxreichmann]

This offers a configPath property to workspace dependency resolution entries as follows:

specVersion: workspace/1.1                      // new specVersion
metadata:
    name: default
dependencyManagement:
    resolutions:
        - path: ../test.library
          configPath: custom-config.yaml        // new customizable paths

(Introducing new specVersion workspace/1.1)

---

Other sub features:

• Improve error handling when path is absolute
• Forbid absolute paths for configPath
• Allow relative paths for configPath (for path it's already allowed)

Closes: #1369
JIRA: CPOUI5FOUNDATION-1233

[maxreichmann]

Kindly asking @KlattG to review the documentation part of this PR already (Workspace.md).

(I didn't add this feature to the usual migrate-v5.md because we planned to downport to v4 too)

[KlattG]

LGTM

[d3xter666]

Please, check the log when you try to build with this new validation/schema:

strict mode: missing type "object" for keyword "properties" at "ui5-workspace.json#/then/properties/dependencyManagement" (strictTypes)
strict mode: missing type "array" for keyword "items" at "ui5-workspace.json#/then/properties/dependencyManagement/properties/resolutions" (strictTypes)
strict mode: missing type "object" for keyword "required" at "ui5-workspace.json#/then/properties/dependencyManagement/properties/resolutions/items/then/not" (strictTypes)

This is from AJV's strict mode

[maxreichmann]

Please, check the log when you try to build with this new validation/schema:

strict mode: missing type "object" for keyword "properties" at "ui5-workspace.json#/then/properties/dependencyManagement" (strictTypes)
strict mode: missing type "array" for keyword "items" at "ui5-workspace.json#/then/properties/dependencyManagement/properties/resolutions" (strictTypes)
strict mode: missing type "object" for keyword "required" at "ui5-workspace.json#/then/properties/dependencyManagement/properties/resolutions/items/then/not" (strictTypes)

This is from AJV's strict mode

Resolved with 4ebdb73

[d3xter666]

This modification leads to a bit strange behaviour that I'm not sure whtether is expected or not.
Here it is:

If you checkout the openui5-sample-app and use a ui5-worspaces.yaml in there to point to the openui5 monorepo locally and inside ui5-worspaces.yaml there is this configPath property with a custom ui5.yaml (it might have different name i.e. ui5-deployment.yaml) configuration, the solution will loop through all of the subpackages within openui5 monorepo and if such a custom file is missing somewhere, the build/serve will fail.

This means, that an external consumer will provide a path to a custom configuration in openui5 repo, expecting this custom configuration to be present everywhere.

A workaround I see is to point individually to every repo.