install: fix strip program stdout and destination hyphen handling #5718 (#5848)

* Fix missing dependency to "process" to make it compile.

* fix issue of not forwarding stdout from strip program

* fix issue of applying "./" redundantly

* cargo fmt

tests/by-util/test_install.rs

@@ -699,7 +699,20 @@ fn test_install_and_strip_with_program_hyphen() {
         .arg("src")
         .arg("-dest")
         .succeeds()
-        .no_stderr();
+        .no_stderr()
+        .stdout_is("./-dest\n");
+
+    scene
+        .ucmd()
+        .arg("-s")
+        .arg("--strip-program")
+        .arg("./no-hyphen")
+        .arg("--")
+        .arg("src")
+        .arg("./-dest")
+        .succeeds()
+        .no_stderr()
+        .stdout_is("./-dest\n");
 }
 
 #[test]