[sonic-snmpagent] Update submodule (#10730)

Include below commits: ``` c75440b 2022-05-02 | Fix: not to use blocking get_all() after keys() (#255) [Qi Luo] ```
sonic-net · May 3, 2022 · 9b55564 · 9b55564
1 parent 96c0d8a
commit 9b55564
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/src/sonic-snmpagent b/src/sonic-snmpagent