when we only filter out fs.ErrNotExist, we get frequent failures
in the local development environment with the following error:
/proc/<pid>/root// is a directory

we seem to think that /proc/<pid>/root// is a executable path,
this happens for short-lived runc processes where /proc/<pid>/maps
has "/" as the pathname for the runc executable itself.

so when we try to open the elf file, we first try to read it from
/proc/<pid>/map_files and (as the process is short lived) when
this fails, we try to open /proc/<pid>/root// which fails with
a "is a directory" error instead of fs.ErrNotExist

to fix this, we just ignore all errors returned by GetElf() and
only log them for debug purposes.

https://github.com/elastic/otel-profiling-agent/blob/0945fe6/libpf/process/process.go#L221-L239

when we fail to initialize the datadog symbol uploader, we set the
uploader to nil, which will cause a panic later on when handling
a new executable for symbol upload.

this sets the uploader to symbolication.NewNoopUploader() when the
datadog uploader is set up, but fails to be initialized.