Add 'on vcpkg' badge

[martinmoene]

Before 'Try it on...', add:

https://vcpkg.link, using package details:

[![Vcpkg](https://img.shields.io/badge/on-vcpkg-blue.svg)](https://vcpkg.link/ports/xxx-lite)

Other possibilities:

[![Vcpkg](https://img.shields.io/badge/on-vcpkg-blue.svg)](https://vcpkg.link/search#q=xxx-lite)
[![Vcpkg](https://img.shields.io/badge/on-vcpkg-blue.svg)](https://vcpkgx.com/?search=%22xxx-lite%22)
[![Vcpkg](https://img.shields.io/badge/on-vcpkg-blue.svg)](https://vcpkgx.com/details.html?package=xxx-lite)

Progress:

• lest
• active-lite
• any-lite
• bit-lite
• boolean-lite
• byte-lite
• expected-lite
• indirect-value-lite
• invoke-lite
• jthread-lte
• observer-ptr-lite
• optional-bare
• optional-lite
• ring-span-lite
• scope-lite
• span-lite
• status-value-lite
• string-view-lite
• type-lite
• value-ptr-lite
• variant-lite

Not to do:

• PM - gsl-lite
• PM - optional-fun-lite