[docs] Build with linkcheck=true (#856)

* [docs] Build with `linkcheck=true`

* [docs] Use empty user agent for linkchecks

* [docs] Require Documenter.jl v1.7

* [docs] Run linkchecks only on CI

---------

Co-authored-by: Mosè Giordano <giordano@users.noreply.github.com>

Author: giordano

docs/Project.toml

@@ -4,6 +4,6 @@ MPI = "da04e1cc-30fd-572f-bb4f-1f8673147195"
 MPIPreferences = "3da0fdf6-3ccc-4f1b-acd9-58baa6c99267"
 
 [compat]
-Documenter = "1"
+Documenter = "1.7"
 MPIPreferences = "0.1"
 MPI = "0.20"

docs/make.jl

@@ -78,6 +78,10 @@ makedocs(
         ],
         "refindex.md",
     ],
+    # Run linkcheck tests only on CI, to speed up building of documentation locally.  If one
+    # wants to run the linkchecks locally they can set the environment variable `CI=true`.
+    linkcheck = get(ENV, "CI", "false") == "true",
+    linkcheck_useragent = nothing,
 )
 
 deploydocs(