LibJS: Change wording of ErrorType::NotA to be independent of context

Currently, we have NotA and NotAn, to be used dependent on whether the
following word begins with a vowel or not. To avoid this, change the
wording on NotA to be independent of this context.

Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.prototype.era.js

@@ -14,7 +14,7 @@ describe("errors", () => {
     test("this value must be a Temporal.Calendar object", () => {
         expect(() => {
             Temporal.Calendar.prototype.era.call("foo");
-        }).toThrowWithMessage(TypeError, "Not a Temporal.Calendar");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.Calendar");
     });
 
     test("argument must be date-like", () => {

Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.prototype.eraYear.js

@@ -14,7 +14,7 @@ describe("errors", () => {
     test("this value must be a Temporal.Calendar object", () => {
         expect(() => {
             Temporal.Calendar.prototype.eraYear.call("foo");
-        }).toThrowWithMessage(TypeError, "Not a Temporal.Calendar");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.Calendar");
     });
 
     test("argument must be date-like", () => {

Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.prototype.fields.js

@@ -27,7 +27,7 @@ describe("errors", () => {
     test("this value must be a Temporal.Calendar object", () => {
         expect(() => {
             Temporal.Calendar.prototype.fields.call("foo");
-        }).toThrowWithMessage(TypeError, "Not a Temporal.Calendar");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.Calendar");
     });
 
     test("iterator values must be strings", () => {

Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.prototype.mergeFields.js

@@ -35,7 +35,7 @@ describe("errors", () => {
     test("this value must be a Temporal.Calendar object", () => {
         expect(() => {
             Temporal.Calendar.prototype.mergeFields.call("foo");
-        }).toThrowWithMessage(TypeError, "Not a Temporal.Calendar");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.Calendar");
     });
 
     test("fields argument must be coercible to object", () => {

Userland/Libraries/LibJS/Tests/builtins/Temporal/Calendar/Calendar.prototype.toString.js

@@ -13,6 +13,6 @@ describe("errors", () => {
     test("this value must be a Temporal.Calendar object", () => {
         expect(() => {
             Temporal.Calendar.prototype.toString.call("foo");
-        }).toThrowWithMessage(TypeError, "Not a Temporal.Calendar");
+        }).toThrowWithMessage(TypeError, "Not an object of type Temporal.Calendar");
     });
 });