fix: increase log rotator line scan limit

In case where gelf/json logging is used, its fairly easy to exceed the 16k limit, resulting in json output being cut up into multiple strings

the result is invalid json lines which can create all kind of badness in the logging server

This fixes https://github.com/hashicorp/nomad/issues/4699

Signed-off-by: Christian Winther <jippignu@gmail.com>

client/driver/logging/rotator.go

@@ -17,7 +17,7 @@ import (
 
 const (
 	// logBufferSize is the size of the buffer.
-	logBufferSize = 32 * 1024
+	logBufferSize = 64 * 1024
 
 	// bufferFlushDuration is the duration at which we flush the buffer.
 	bufferFlushDuration = 100 * time.Millisecond
@@ -26,7 +26,7 @@ const (
 	// lines when approaching the end of the file to avoid a log line being
 	// split between two files. Any single line that is greater than this limit
 	// may be split.
-	lineScanLimit = 16 * 1024
+	lineScanLimit = 32 * 1024
 
 	// newLineDelimiter is the delimiter used for new lines.
 	newLineDelimiter = '\n'