fix: build failed when registry address with port

[chlins]

Fixes: #46

This pull request includes various fixes and improvements across multiple files in the pkg/backend and pkg/storage directories. The changes mainly focus on correcting typos, ensuring proper error handling, and updating import statements for better code organization.

Typo Fixes:

• Corrected typos in error messages within the Build and Extract methods in pkg/backend/build.go and pkg/backend/extract.go respectively. [1] [2]

Error Handling Improvements:

• Updated error handling in the Process method for multiple processors (licenseProcessor, modelProcessor, modelConfigProcessor, and readmeProcessor) to return the actual error instead of nil in case of a failure. [1] [2] [3] [4]

Import Statement Updates:

• Reorganized import statements in pkg/backend/processor/license.go, pkg/backend/processor/model.go, pkg/backend/processor/model_config.go, and pkg/backend/processor/readme.go to maintain consistency and readability. [1] [2] [3] [4]

New Functionality:

• Added an initialization function in pkg/storage/distribution/distribution.go to modify the PathRegexp to support repository names that include a port.

[gaius-qi]

LGTM