docs: fix incorrect example in Don't ignore rejected promises section

The previous Bad example called getdata() (lowercase 'd') inconsistently,
and both Bad and Good examples looked structurally similar, making it
unclear what the actual anti-pattern was.

Changes:
- Fix inconsistent casing: getdata() -> getData() in both examples
- Add an inline comment in the Bad example to explain why console.log()
  alone is insufficient — it silently swallows the error without any
  visible action or user notification
- Update comment in Good example from 'more noisy' to 'more visible'
  which is clearer and less pejorative

This makes the distinction between the two examples obvious:
the Bad example shows error handling that silently swallows details,
while the Good example shows meaningful error handling strategies.

Closes ryanmcdermott#718

Author: Eduardo Bar

README.md

@@ -2050,24 +2050,24 @@ from `try/catch`.
 **Bad:**
 
 ```javascript
-getdata()
+getData()
   .then(data => {
     functionThatMightThrow(data);
   })
   .catch(error => {
-    console.log(error);
+    console.log(error); // Just logging is not enough — the error is silently swallowed
   });
 ```
 
 **Good:**
 
 ```javascript
-getdata()
+getData()
   .then(data => {
     functionThatMightThrow(data);
   })
   .catch(error => {
-    // One option (more noisy than console.log):
+    // One option (more visible than console.log):
     console.error(error);
     // Another option:
     notifyUserOfError(error);