fixes#24552
Could also implement `{.used.}` for imports but this wouldn't be
backwards compatible. The same problem as #24552 also exists for
`{.hint[XDeclaredButNotUsed].}` but this isn't as much of a problem
since `{.used.}`/`{.push used.}` exist.
Refs #24158
Fixes the line info of the module symbol (cases like `import as` and
grouped imports had wrong line info). Since that symbol's line info is
now used for the warnings, there isn't a separate line info stored for
`unusedImports`
Examples of fixed cases
```nim
import strutils as test #[
^ before
^ after ]#
# This case was fixed by #24158, but only for unused imports
import std/[strutils, strutils] #[
^ before
^ after ]#
from strutils import split #[
^ before
^ after ]#
```
* fixes#22065; do not search path for "./"
* simplify
* fixes
* fixes
* allow ".."
* cleanup
* add a test case
* slightly modify the import
* adds a changelog
