Create blog post template

[zenlex]

Related to CI/CD issue #113.

• Create a blog.example.md file at the root of the project with the frontmatter fields listed in Create GH Actions workflow for templating a blog post #113.

[helmturner]

The shape of the frontmatter should reflect the following object:

type frontmatter = {
    description?: string | null | undefined;
    updated?: string | null | undefined;
    author: string;
    title: string;
    date: string;
}