update tests to work with SystemError again

Author: fatteneder

test/loading.jl

@@ -650,9 +650,9 @@ end
 # normalization of paths by include (#26424)
 @test begin
     exc = try; include("./notarealfile.jl"); "unexpectedly reached!"; catch exc; exc; end
-    @test exc isa ArgumentError
-    exc.msg
-end == "including $(repr(joinpath(@__DIR__, "notarealfile.jl"))): No such file"
+    @test exc isa SystemError
+    exc.prefix
+end == "including file $(repr(joinpath(@__DIR__, "notarealfile.jl"))): No such file"
 
 old_act_proj = Base.ACTIVE_PROJECT[]
 pushfirst!(LOAD_PATH, "@")
@@ -1542,7 +1542,7 @@ end
         end
 
         file = joinpath(depot, "dev", "non-existent.jl")
-        @test_throws ArgumentError("including $(repr(file)): No such file") include(file)
+        @test_throws SystemError("including file $(repr(file)): No such file") include(file)
         touch(file)
         @test include_dependency(file) === nothing
         chmod(file, 0x000)
@@ -1552,7 +1552,7 @@ end
             @test include_dependency(dir) === nothing
             dir
         end
-        @test_throws ArgumentError("including $(repr(dir)): No such file or directory") include_dependency(dir)
+        @test_throws SystemError("including $(repr(dir)): No such file or directory") include_dependency(dir)
     end
 end