* Update CubeL4 to 1.13.0
 * Rebuild OurTLS with `-DMBEDTLS_X509_CA_CHAIN_ON_DISK`
 * Add `-Wextra` and fix build issues

CL: Update STM32 build image

PUBLISHED_FROM=a7eacff7580bab6c6e40bdaf6164df575a717c55