Rename tests and add short test description

Author: VirrageS

src/test/ui/issues/issue-66923.rs src/test/ui/issues/issue-66923-show-error-for-correct-call.rs

@@ -1,13 +1,15 @@
+// This test checks that errors are showed for lines with `collect` rather than `push` method.
+
 fn main() {
     let v = vec![1_f64, 2.2_f64];
     let mut fft: Vec<Vec<f64>> = vec![];
 
     let x1: &[f64] = &v;
     let x2: Vec<f64> = x1.into_iter().collect();
-    //~^ ERROR a collection of type
+    //~^ ERROR a value of type
     fft.push(x2);
 
     let x3 = x1.into_iter().collect::<Vec<f64>>();
-    //~^ ERROR a collection of type
+    //~^ ERROR a value of type
     fft.push(x3);
 }

src/test/ui/issues/issue-66923-show-error-for-correct-call.stderr

@@ -0,0 +1,19 @@
+error[E0277]: a value of type `std::vec::Vec<f64>` cannot be built from an iterator over elements of type `&f64`
+  --> $DIR/issue-66923-show-error-for-correct-call.rs:8:39
+   |
+LL |     let x2: Vec<f64> = x1.into_iter().collect();
+   |                                       ^^^^^^^ value of type `std::vec::Vec<f64>` cannot be built from `std::iter::Iterator<Item=&f64>`
+   |
+   = help: the trait `std::iter::FromIterator<&f64>` is not implemented for `std::vec::Vec<f64>`
+
+error[E0277]: a value of type `std::vec::Vec<f64>` cannot be built from an iterator over elements of type `&f64`
+  --> $DIR/issue-66923-show-error-for-correct-call.rs:12:29
+   |
+LL |     let x3 = x1.into_iter().collect::<Vec<f64>>();
+   |                             ^^^^^^^ value of type `std::vec::Vec<f64>` cannot be built from `std::iter::Iterator<Item=&f64>`
+   |
+   = help: the trait `std::iter::FromIterator<&f64>` is not implemented for `std::vec::Vec<f64>`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0277`.