A few fixes

Author: DilumAluthge

src/VersionsJSONUtil.jl

@@ -163,11 +163,11 @@ function get_new_headinfo_for_url(url::URI)
     etag = get(headers, "ETag", "")
     last_modified = get(headers, "Last-Modified", "")
     if isempty(strip(etag))
-        @warn "Got empty new ETag for URL: $new_etag"
+        @warn "Got empty new ETag for URL: $etag"
         etag = nothing
     end
     if isempty(strip(last_modified))
-        @warn "Got empty new ETag for URL: $new_etag"
+        @warn "Got empty new Last-Modified for URL: $last_modified"
         last_modified = nothing
     end
     head_info = HeadInfo(; etag, last_modified)