[librsvg: 18/30] error: fix a clippy suggestion

[Federico Mena Quintero <federico src gnome org>]

commit 704174379c42c9a7f0a85633d885e5d4d3cb647f
Author: Paolo Borelli <pborelli gnome org>
Date:   Sat Dec 26 14:39:33 2020 +0100

    error: fix a clippy suggestion

 src/error.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/src/error.rs b/src/error.rs
index 22632fce..f3d1b246 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -253,7 +253,7 @@ impl<'i, O> AttributeResultExt<O> for Result<O, ParseError<'i>> {
                 ParseErrorKind::Basic(BasicParseErrorKind::UnexpectedToken(tok)) => {
                     let mut s = String::from("unexpected token '");
                     tok.to_css(&mut s).unwrap(); // FIXME: what do we do with a fmt::Error?
-                    s.push_str("'");
+                    s.push('\'');
 
                     ElementError {
                         attr,