[lldb/Format] Make progress count show thousands separators (NFC) (llvm#137446)

This patch changes the progress count formatting show thousands
separator making it easier to read big numbers.

Signed-off-by: Med Ismail Bennani <[email protected]>

Author: medismailben

lldb/source/Core/FormatEntity.cpp

@@ -1960,7 +1960,7 @@ bool FormatEntity::Format(const Entry &entry, Stream &s,
     if (Target *target = Target::GetTargetFromContexts(exe_ctx, sc)) {
       if (auto progress = target->GetDebugger().GetCurrentProgressReport()) {
         if (progress->total != UINT64_MAX) {
-          s.Format("[{0}/{1}]", progress->completed, progress->total);
+          s.Format("[{0:N}/{1:N}]", progress->completed, progress->total);
           return true;
         }
       }