pkg/environment: Remove some file-based functions

This commit removes certain file-based functions from 'pkg/environment',
continuing the migration to entirely remove the package.

pkg/environment/environment.go

@@ -3,7 +3,6 @@ package environment
 import (
 	"io"
 	"io/fs"
-	"time"
 )
 
 // Environment represents an environment that a program can run it.
@@ -11,31 +10,9 @@ import (
 type Environment interface {
 	isEnv()
 
-	GetEnv(name string) string
-
-	Stat(path string) (fs.FileInfo, error)
-	Lstat(path string) (fs.FileInfo, error)
-
-	Readlink(path string) (string, error)
-	Symlink(oldname, newname string) error
-
-	ReadDir(name string) ([]fs.DirEntry, error)
-
-	Open(path string) (fs.File, error)
-	Chtimes(name string, atime time.Time, mtime time.Time) error
-	SameFile(f1, f2 fs.FileInfo) bool
-
 	Create(path string, mode fs.FileMode) (WritableFile, error)
-
 	Mkdir(path string, mode fs.FileMode) error
 	MkdirAll(path string, mode fs.FileMode) error
-
-	Remove(path string) error
-	RemoveAll(path string) error
-
-	WalkDir(root string, fn fs.WalkDirFunc) error
-
-	Abs(path string) (string, error)
 }
 
 type WritableFile interface {