Use ranges

C++20 brought us std::ranges for a lot of algorithms.  Most of these
conversions were done using comby, similar to:

```
comby -verbose 'std::lower_bound(:[a].begin(),:[b].end(),:[c])' 'std::ranges::lower_bound(:[a], :[c])' $(git ls-files | grep "\.[hc]\(pp\)\?$") -in-place
```

Change-Id: I0c99c04e9368312555c08147d474ca93a5959e8d
Signed-off-by: Ed Tanous <edtanous@google.com>
diff --git a/include/multipart_parser.hpp b/include/multipart_parser.hpp
index 5ac196d..f707abf 100644
--- a/include/multipart_parser.hpp
+++ b/include/multipart_parser.hpp
@@ -4,6 +4,7 @@
 
 #include <boost/beast/http/fields.hpp>
 
+#include <ranges>
 #include <string>
 #include <string_view>
 
@@ -224,7 +225,7 @@
   private:
     void indexBoundary()
     {
-        std::fill(boundaryIndex.begin(), boundaryIndex.end(), 0);
+        std::ranges::fill(boundaryIndex, 0);
         for (const char current : boundary)
         {
             boundaryIndex[static_cast<unsigned char>(current)] = true;