GitLab Flavored Markdown references in personal snippets

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You can now use GitLab Flavored Markdown (GFM) references with personal snippets in two ways:

• GitLab processes GFM references inside personal snippet descriptions and comments, just like in project snippets and other areas of GitLab.
• You can reference a personal snippet from anywhere GFM is supported, such as comments and issue or merge request descriptions, using the $<id> syntax that already works for project snippets.

Because snippet IDs are unique across personal and project snippets, each ID resolves to a single snippet.