flux-overlay(1): correct punctuation

Problem: a > character is used where a period should be.

Fix punctuation.

Author: garlick

doc/man1/flux-overlay.rst

@@ -151,7 +151,7 @@ OPTIONS
 
 **-w, --wait=STATE**
    Wait until sub-tree enters *STATE* before reporting (full, partial, offline,
-   degraded, lost)>
+   degraded, lost).
 
 
 RESOURCES