src: doc: remove more double-space typos

Found with git grep -E '[a-z]  [a-z]'

doc/userguide/devguide/codebase/code-style.rst

@@ -538,7 +538,7 @@ We use ``/* foobar */`` style and try to avoid ``//`` style.
 File names
 **********
 
-File names are all lowercase and have a .c. .h  or .rs (Rust) extension.
+File names are all lowercase and have a .c .h or .rs (Rust) extension.
 
 Most files have a _subsystem_ prefix, e.g. ``detect-dsize.c, util-ip.c``
 

src/detect-engine-event.c

@@ -364,7 +364,6 @@ static int EngineEventTestParse01 (void)
     PASS;
 }
 
-
 /**
  * \test EngineEventTestParse02 is a test for a valid upper + lower case decode-event value
  */

src/util-unittest.c

@@ -297,7 +297,8 @@ void UtRunModeRegister(void)
 static int UtSelftestTrue(void)
 {
     if (1)return 1;
-    else  return 0;
+    else
+        return 0;
 }
 
 /** \brief False test
@@ -308,7 +309,8 @@ static int UtSelftestTrue(void)
 static int UtSelftestFalse(void)
 {
     if (0)return 0;
-    else  return 1;
+    else
+        return 1;
 }
 
 /** \brief Run self tests