in for, loop, while, auto print final value in each iteration (#7433)

# Description

Fixes: #7404 
Fixes: #7402 

## About change
In `eval_block`, all pipelines(or called statements?) result will be
printed except the last one, the last one is returned by `eval_block`
function.

So if we want to print the last statement in eval block, we just need to
print that value.

# User-Facing Changes

### for
```
❯ for _ in 1..2 { echo "a" }
a
a
```

### while
```
❯ mut x = 1; while $x < 3 { $x = $x + 1; echo bb; }
bb
bb
```

### loop
```
❯ mut total = 0; loop {
∙     if $total > 1 {
∙         break
∙     } else {
∙         $total += 1
∙     }
∙     echo 3
∙ }
3
3
```

# Tests + Formatting

Don't forget to add tests that cover your changes.

Make sure you've run and fixed any issues with these commands:

- `cargo fmt --all -- --check` to check standard code formatting (`cargo
fmt --all` applies these changes)
- `cargo clippy --workspace -- -D warnings -D clippy::unwrap_used -A
clippy::needless_collect` to check that you're using the standard code
style
  - `cargo test --workspace` to check that all tests pass

# After Submitting

If your PR had any user-facing changes, update [the
documentation](https://github.com/nushell/nushell.github.io) after the
PR is merged, if necessary. This will help us keep the docs up to date.

crates/nu-command/tests/commands/mod.rs

@@ -24,6 +24,7 @@ mod export_def;
 mod find;
 mod first;
 mod flatten;
+mod for_;
 mod format;
 mod g;
 mod get;
@@ -41,6 +42,7 @@ mod last;
 mod length;
 mod let_;
 mod lines;
+mod loop_;
 mod ls;
 mod math;
 mod merge;