Update git submodules

* Update docs/submodules/policy/distribution.git from branch 'master'
  to 7783a2ef0d71c6379a1d53258cd3c01eba391210
  - Add curly braces in shell script file
    
    According to comment:
    https://gerrit.onap.org/r/c/policy/xacml-pdp/+/90495/1/packages/policy-xacmlpdp-docker/src/main/docker/policy-pdpx.sh#43
    
    Issue-ID: POLICY-1702
    Change-Id: Ie7c37a07dfc33f6b6bca70d9f9c2cb4cfb3377f5
    Signed-off-by: shaoqiu <tim.huang@est.tech>
    
diff --git a/docs/submodules/policy/distribution.git b/docs/submodules/policy/distribution.git
index 4429dc7..7783a2e 160000
--- a/docs/submodules/policy/distribution.git
+++ b/docs/submodules/policy/distribution.git
@@ -1 +1 @@
-Subproject commit 4429dc73ff9560ac6531bb6a58cbc9e2254325bc
+Subproject commit 7783a2ef0d71c6379a1d53258cd3c01eba391210