Symbolize clang's sanitizer stacks

llvm-symbolizer is needed to symbolize (convert the raw addresses to
function names and line numbers) the offending stacks.

Before
======

```
==214==WARNING: invalid path to external symbolizer!
==214==WARNING: Failed to use and restart external symbolizer!
    #0 0x559a1f2cb4b7  (/app/test/test+0x1614b7)
    #1 0x559a1f2c9df1  (/app/test/test+0x15fdf1)
    #2 0x559a1f2b09ce  (/app/test/test+0x1469ce)
    #3 0x559a1f2cd284  (/app/test/test+0x163284)
    #4 0x7ff53fec509a  (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
    #5 0x559a1f1df5a9  (/app/test/test+0x755a9)
```

With this commit
================

```
==264==WARNING: MemorySanitizer: use-of-uninitialized-value
    #0 0x5627376334b7 in greatest_memory_equal_cb (/app/test/test+0x1614b7)
    #1 0x562737631df1 in greatest_do_assert_equal_t (/app/test/test+0x15fdf1)
    #2 0x5627376189ce in build_auth_packet_test (/app/test/test+0x1469ce)
    #3 0x562737635284 in main (/app/test/test+0x163284)
    #4 0x7f04462a609a in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x2409a)
    #5 0x5627375475a9 in _start (/app/test/test+0x755a9)
```

Signed-off-by: Francisco Javier Honduvilla Coto <javierhonduco@gmail.com>

Dockerfile

@@ -3,7 +3,7 @@ ARG RUBY_VERSION=3.2
 FROM ${DISTRIBUTION}
 LABEL maintainer="github@github.com"
 
-RUN apt-get update -qq && DEBIAN_FRONTEND=noninteractive apt-get install --no-install-recommends -y build-essential ca-certificates wget libssl-dev default-libmysqlclient-dev clang clang-tools valgrind netcat
+RUN apt-get update -qq && DEBIAN_FRONTEND=noninteractive apt-get install --no-install-recommends -y build-essential ca-certificates wget libssl-dev default-libmysqlclient-dev clang clang-tools llvm valgrind netcat
 
 RUN update-ca-certificates