chore: remove cacheable field from ScriptManager log

Cacheable for ScriptManager means something very specific (should the js.Context
cache the module for subsequent loads). With HTTP caching coming, I'm removing
this field from the ScriptManager logs because (a) it isn't very useful anyways
and (b) it doesn't mean what most people who see it would think it means.

src/browser/ScriptManagerBase.zig

@@ -915,7 +915,6 @@ pub const Script = struct {
         log.info(.browser, "executing script", .{
             .src = url,
             .kind = fe.kind,
-            .cacheable = cacheable,
         });
 
         var ls: js.Local.Scope = undefined;
@@ -941,7 +940,6 @@ pub const Script = struct {
                     .err = err,
                     .src = url,
                     .kind = fe.kind,
-                    .cacheable = cacheable,
                 });
                 self.executeCallback(comptime .wrap("error"));
                 return;
@@ -999,7 +997,6 @@ pub const Script = struct {
         log.warn(.js, "eval script", .{
             .url = url,
             .caught = caught,
-            .cacheable = cacheable,
         });
 
         if (try_catch.exceptionValue()) |exc| {