Allow running vscode remote server in environments where there are multiple libc or libc++ candidate paths. For determining the library version, use the first one reported in ldconfig -p.

For context, I'm running vscode server in a container with two libc packages: default one from libc6:amd64 package, and another from libc6-prof:amd64 (compiled with frame pointers) - both targeting x86:

# /sbin/ldconfig -p | grep libc.so.6
        libc.so.6 (libc6,x86-64, OS ABI: Linux 3.2.0) => /lib/libc6-prof/x86_64-linux-gnu/libc.so.6
        libc.so.6 (libc6,x86-64, OS ABI: Linux 3.2.0) => /lib/x86_64-linux-gnu/libc.so.6
        libc.so.6 (libc6, OS ABI: Linux 3.2.0) => /lib32/libc.so.6

Currently, the script fails silently. $libc_path contains two paths, and readlink -f "$libc_path" fails with exit code 1.