tsort: add example with a string (#10157)

* tsort: Add an actual example with a string

The current example doesn't show what path/to/file should be like (or provide a concrete example)

* Apply placeholder

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>

* Add - e to the echo cmd

Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

---------

Co-authored-by: K.B.Dharun Krishna <kbdharunkrishna@gmail.com>
Co-authored-by: Lena <126529524+acuteenvy@users.noreply.github.com>

pages/common/tsort.md

@@ -7,3 +7,7 @@
 - Perform a topological sort consistent with a partial sort per line of input separated by blanks:
 
 `tsort {{path/to/file}}`
+
+- Perform a topological sort consistent on strings:
+
+`echo -e "{{UI Backend\nBackend Database\nDocs UI}}" | tsort`