tests/functional2/lang: Migrate path-string-interpolation

Change-Id: I6f5d1830363c8dff4fa6b368550c8c4247766609

tests/functional/lang/eval-okay-path-string-interpolation.exp

@@ -1 +0,0 @@
-{ absolute = /foo; expr = /pwd/foo/bar; home = /fake-home/foo; notfirst = /pwd/bar/foo; simple = /pwd/foo; slashes = /foo/bar; surrounded = /pwd/a-foo-b; }

tests/functional2/lang/path-string-interpolation/eval-okay.out.exp

@@ -0,0 +1 @@
+{ absolute = /foo; expr = /pwd/foo/bar; home = /pwd/foo; notfirst = /pwd/bar/foo; simple = /pwd/foo; slashes = /foo/bar; surrounded = /pwd/a-foo-b; }