Propose to add content to 103-docker-and-oci.md

The OCI-specification has three core specifications while on the description written only two are mentioned. 

I added the *Distribution Specification (distribution-spec)*.

According to the website, the distro-spec defines a standardized API protocol for distributing container images and other content. It is primarly designed to ensure interoperability and consistency across different container registries and tools, regardless of their specific implementation.

I attach below links to the website of OCI and the github repo
- [https://github.com/opencontainers/distribution-spec](On the github repo of the OCI) 
- [https://opencontainers.org/about/overview/](Website of the OCI)

src/data/roadmaps/docker/content/100-introduction/103-docker-and-oci.md

@@ -8,12 +8,15 @@ The [Open Container Initiative (OCI)](https://opencontainers.org/) is a Linux Fo
 
 ### OCI Specifications
 
-OCI has two main specifications:
+OCI has three main specifications:
 
 - **Runtime Specification (runtime-spec):** It defines the specification for executing a container via an isolation technology, like a container engine. The container runtime built by Docker, called 'containerd', has guided the development of the OCI runtime-spec.
 
 - **Image Specification (image-spec):** It defines the container image format, which describes the contents of a container and can be run by a compliant runtime. Docker's initial image format has led to the creation of the OCI image-spec.
 
+- **Distribution Specification (distribution-spec):** It defines defines an API protocol to facilitate and standardize the distribution of content. Docker's existing registry API served as a starting point and heavily influenced the design of the OCI Distro Spec. 
+
+
 ### Compatibility between Docker and OCI
 
 Docker remains committed to supporting the OCI specifications and, since its involvement in OCI, has continuously updated its software to be compliant with OCI standards. Docker's containerd runtime and image format are fully compatible with OCI specifications, enabling Docker containers to be run by other OCI-compliant container runtimes and vice versa.