fix(testing-tools): typo

Author: razvan

testing-tools/Dockerfile

@@ -50,7 +50,7 @@ microdnf update
 microdnf install \
   `# This installs kinit needed in kerberos tests.` \
   krb5-workstation \
-  krb5-devel
+  krb5-devel \
   gcc \
   make \
   pkg-config \