Update git submodules

* Update docs/submodules/so.git from branch 'master'
  to 074c0ebe9c1a0db0a5e0cc936898c35569ff4029
  - Merge "Changed constants collections to immutable"
  - Changed constants collections to immutable

    Fix to three Sonar vulnerabilites.
    Changed mutable collections of constants (exposed by utility class) to
    immutable.

    Change-Id: I3b301eac20b52df72a6d1318483b7b931e750313
    Issue-ID: SO-1794
    Signed-off-by: Witold Ficio Kopel <w.kopel@samsung.com>

diff --git a/docs/submodules/so.git b/docs/submodules/so.git
index 14a0406..074c0eb 160000 (submodule)
--- a/docs/submodules/so.git
+++ b/docs/submodules/so.git
@@ -1 +1 @@
-Subproject commit 14a0406521ec15e259729dcd27e9aaac14517e66
+Subproject commit 074c0ebe9c1a0db0a5e0cc936898c35569ff4029