Add libpam to docker scripts

pam-ipmi requires libpam, therefore
it is required to be added for the CI
to succeed

Change-Id: I020da1333a0d391155b1e2721936dd023fd9b3cb
Signed-off-by: Richard Marian Thomaiyar <richard.marian.thomaiyar@linux.intel.com>
diff --git a/build-unit-test-docker.sh b/build-unit-test-docker.sh
index 771d2d8..ef3045c 100755
--- a/build-unit-test-docker.sh
+++ b/build-unit-test-docker.sh
@@ -105,7 +105,8 @@
     libsnmp-dev \
     valgrind \
     valgrind-dbg \
-    lcov
+    lcov \
+    libpam0g-dev
 
 RUN pip install inflection
 RUN pip install pycodestyle