Remove some unnecessary parens in assert! conditions

While working on #122661, some of these started triggering our "unnecessary parens" lints due to a change in the `assert!` desugaring. A cursory search identified a few more. Some of these have been carried from before 1.0, were a bulk rename from the previous name of `assert!` left them in that state. I went and removed as many of these unnecessary parens as possible in order to have fewer annoyances in the future if we make the lint smarter.

library/coretests/tests/bool.rs

@@ -71,14 +71,14 @@ fn test_bool() {
 #[test]
 pub fn test_bool_not() {
     if !false {
-        assert!((true));
+        assert!(true);
     } else {
-        assert!((false));
+        assert!(false);
     }
     if !true {
-        assert!((false));
+        assert!(false);
     } else {
-        assert!((true));
+        assert!(true);
     }
 }
 

library/coretests/tests/ptr.rs

@@ -42,11 +42,11 @@ fn test() {
         let mut v1 = vec![0u16, 0u16, 0u16];
 
         copy(v0.as_ptr().offset(1), v1.as_mut_ptr().offset(1), 1);
-        assert!((v1[0] == 0u16 && v1[1] == 32001u16 && v1[2] == 0u16));
+        assert!(v1[0] == 0u16 && v1[1] == 32001u16 && v1[2] == 0u16);
         copy(v0.as_ptr().offset(2), v1.as_mut_ptr(), 1);
-        assert!((v1[0] == 32002u16 && v1[1] == 32001u16 && v1[2] == 0u16));
+        assert!(v1[0] == 32002u16 && v1[1] == 32001u16 && v1[2] == 0u16);
         copy(v0.as_ptr(), v1.as_mut_ptr().offset(2), 1);
-        assert!((v1[0] == 32002u16 && v1[1] == 32001u16 && v1[2] == 32000u16));
+        assert!(v1[0] == 32002u16 && v1[1] == 32001u16 && v1[2] == 32000u16);
     }
 }