[docs] Add more notable users and improve query for searching downstream packages (#91)

* [docs] Improve query for searching packages using ParallelTestRunner

This includes packages which have
```
using Test, ParallelTestRunner
```
rather than exactly
```
using ParallelTestRunner
```

* [docs] Add links to some more packages using ParallelTestRunner

Author: giordano

docs/src/index.md

@@ -141,16 +141,20 @@ Each test file runs in its own isolated module, so you don't need to worry about
 
 ## Packages using ParallelTestRunner.jl
 
-There are a few packages already [using `ParallelTestRunner.jl`](https://github.com/search?q=%22using+ParallelTestRunner%22+language%3AJulia++NOT+is%3Aarchived+NOT+is%3Afork+path%3A%2F%5Etest%5C%2Fruntests.jl%2F&type=code) to parallelize their tests, you can look at their setups if you need inspiration to move your packages as well:
+There are a few packages already [using `ParallelTestRunner.jl`](https://github.com/search?q=%2Fusing.*+ParallelTestRunner%2F+language%3AJulia++NOT+is%3Aarchived+NOT+is%3Afork+path%3A%2F%5Etest%5C%2Fruntests.jl%2F&type=code) to parallelize their tests, you can look at their setups if you need inspiration to move your packages as well.
+Among them are:
 
+* [`AMDGPU.jl`](https://github.com/JuliaGPU/AMDGPU.jl/blob/master/test/runtests.jl)
 * [`ApproxFun.jl`](https://github.com/JuliaApproximation/ApproxFun.jl/blob/master/test/runtests.jl)
 * [`BlockArrays.jl`](https://github.com/JuliaArrays/BlockArrays.jl/blob/master/test/runtests.jl)
 * [`CuNESSie.jl`](https://github.com/tkemmer/CuNESSie.jl/blob/master/test/runtests.jl)
+* [`cuTile.jl`](https://github.com/JuliaGPU/cuTile.jl/blob/main/test/runtests.jl)
 * [`Enzyme.jl`](https://github.com/EnzymeAD/Enzyme.jl/blob/main/test/runtests.jl)
 * [`GPUArrays.jl`](https://github.com/JuliaGPU/GPUArrays.jl/blob/master/test/runtests.jl)
 * [`GPUCompiler.jl`](https://github.com/JuliaGPU/GPUCompiler.jl/blob/master/test/runtests.jl)
 * [`HyperHessians.jl`](https://github.com/KristofferC/HyperHessians.jl/blob/master/test/runtests.jl)
 * [`Metal.jl`](https://github.com/JuliaGPU/Metal.jl/blob/main/test/runtests.jl)
+* [`Reactant.jl`](https://github.com/EnzymeAD/Reactant.jl/blob/main/test/runtests.jl)
 * [`WCS.jl`](https://github.com/JuliaAstro/WCS.jl/blob/master/test/runtests.jl)
 
 ## Inspiration