Revert "Harden Linux manager executable resolution for elevation (#4621)"

This reverts commit 335578e.

Author: GabrielDuf

src/UniGetUI.PackageEngine.Managers.Apt/Apt.cs

@@ -52,8 +52,8 @@ public Apt()
 
     public override IReadOnlyList<string> FindCandidateExecutableFiles()
     {
-        var candidates = new List<string>();
-        foreach (var path in new[] { "/usr/bin/apt", "/bin/apt" })
+        var candidates = new List<string>(CoreTools.WhichMultiple("apt"));
+        foreach (var path in new[] { "/usr/bin/apt", "/usr/local/bin/apt" })
         {
             if (File.Exists(path) && !candidates.Contains(path))
                 candidates.Add(path);

src/UniGetUI.PackageEngine.Managers.Dnf/Dnf.cs

@@ -55,8 +55,13 @@ public Dnf()
 
     public override IReadOnlyList<string> FindCandidateExecutableFiles()
     {
-        var candidates = new List<string>();
-        foreach (var path in new[] { "/usr/bin/dnf5", "/usr/bin/dnf", "/bin/dnf5", "/bin/dnf" })
+        var candidates = new List<string>(CoreTools.WhichMultiple("dnf5"));
+        foreach (var path in CoreTools.WhichMultiple("dnf"))
+        {
+            if (!candidates.Contains(path))
+                candidates.Add(path);
+        }
+        foreach (var path in new[] { "/usr/bin/dnf5", "/usr/bin/dnf", "/usr/local/bin/dnf" })
         {
             if (File.Exists(path) && !candidates.Contains(path))
                 candidates.Add(path);

src/UniGetUI.PackageEngine.Managers.Pacman/Pacman.cs

@@ -51,8 +51,8 @@ public Pacman()
 
     public override IReadOnlyList<string> FindCandidateExecutableFiles()
     {
-        var candidates = new List<string>();
-        foreach (var path in new[] { "/usr/bin/pacman", "/bin/pacman" })
+        var candidates = new List<string>(CoreTools.WhichMultiple("pacman"));
+        foreach (var path in new[] { "/usr/bin/pacman", "/usr/local/bin/pacman" })
         {
             if (File.Exists(path) && !candidates.Contains(path))
                 candidates.Add(path);