style(3p/nix): Add braces around single-line conditionals r/771

These were not caught by the previous clang-tidy invocation, but were
instead sorted out using amber[0] as such:

    ambr --regex 'if (\(.+\))\s([a-z].*;)' 'if $1 { $2 }'

[0]: https://github.com/dalance/amber

1 files changed, 3 insertions, 1 deletions

diff --git a/third_party/nix/src/nix/sigs.cc b/third_party/nix/src/nix/sigs.cc
index cc9d579909e2..d548f5445fe3 100644
--- a/third_party/nix/src/nix/sigs.cc
+++ b/third_party/nix/src/nix/sigs.cc
@@ -67,7 +67,9 @@ struct CmdCopySigs : StorePathsCommand {
             continue;
 
           for (auto& sig : info2->sigs)
-            if (!info->sigs.count(sig)) newSigs.insert(sig);
+            if (!info->sigs.count(sig)) {
+              newSigs.insert(sig);
+            }
         } catch (InvalidPath&) {
         }
       }