Fix use of deleted function

Compilation fails due to implicit cast to QChar

Compilation on void linux (qt 5.15.3+20210429) fails with
csync_exclude.cpp:489:34: error: use of deleted function 'QCharRef& QCharRef::operator=(char)'

1 files changed, 1 insertions, 1 deletions

diff --git a/src/csync/csync_exclude.cpp b/src/csync/csync_exclude.cpp
index 586035346..c5c7bbccf 100644
--- a/src/csync/csync_exclude.cpp
+++ b/src/csync/csync_exclude.cpp
@@ -488,7 +488,7 @@ QString ExcludedFiles::convertToRegexpSyntax(QString exclude, bool wildcardsMatc
             // Translate [! to [^
             QString bracketExpr = exclude.mid(i, j - i + 1);
             if (bracketExpr.startsWith(QLatin1String("[!")))
-                bracketExpr[1] = '^';
+                bracketExpr[1] = QLatin1Char('^');
             regex.append(bracketExpr);
             i = j;
             break;