feat: use "git config core.hooksPath" instead of symlinking

BREAKING CHANGE: this note is more to signify that this change can
have unexpected consequences on repositories that used any previous
version where GHooks used to use symbolic links. While I can't
think of anything that can go wrong with simply re-setting what the
local config for hooksPath is, this note is meant to be a trigger
for a major version change and to give a potential migration path:

- Remove the symlinked directory (and potentially re-create an
  empty directory: `rm -rf .git/hooks && mkdir .git/hooks`;
- Run GHooks' install task: `./gradlew installGitHooks`;

src/main/kotlin/com/gtramontina/ghooks/GHooks.kt

@@ -1,23 +1,16 @@
 package com.gtramontina.ghooks
 
-import org.apache.commons.io.FileUtils.forceDelete
 import org.gradle.api.Plugin
 import org.gradle.api.Project
-import java.nio.file.Files.createSymbolicLink
-import java.nio.file.Files.exists
 import java.nio.file.Files.isDirectory
-import java.nio.file.Files.isSymbolicLink
-import java.nio.file.Files.readSymbolicLink
-import java.nio.file.Path
 
 class GHooks : Plugin<Project> {
     companion object {
         private const val GIT_HOOKS_TARGET = ".githooks"
-        private const val GIT_HOOKS_SOURCE = ".git/hooks"
         private const val DESCRIPTION = "Installs the configured Git hooks."
         private const val GROUP = "git hooks"
         private const val TASK_NAME = "installGitHooks"
-        private const val GIT_CDUP = "git rev-parse --show-cdup"
+        private const val GIT_CONFIG_HOOKS = "git config core.hooksPath $GIT_HOOKS_TARGET"
         private const val GIT_HOOKS_TARGET_WARNING = """
 
             Something went wrong while installing your Git hooks.
@@ -46,22 +39,8 @@ class GHooks : Plugin<Project> {
                 task.logger.warn(GIT_HOOKS_TARGET_WARNING.trimIndent()).also { return@task }
             }
 
-            GIT_CDUP.exec(root)
-                .thenApply { root.resolve(it.trim()) }
-                .thenApply { it.resolve(GIT_HOOKS_SOURCE).toPath() }
-                .thenAccept { it.symLinkTo(it.parent.relativize(target)) }
+            GIT_CONFIG_HOOKS.exec(root)
                 .exceptionally { task.logger.warn(GIT_WARNING.trimIndent(), it).run { throw it } }
         }
     }
-
-    private fun Path.symLinkTo(target: Path) {
-        if (isSymLinkTo(target)) return
-        deleteIfExists().also { createSymbolicLink(this, target) }
-    }
-
-    private fun Path.isSymLinkTo(target: Path) = exists(this) &&
-        isSymbolicLink(this) &&
-        readSymbolicLink(this) == target
-
-    private fun Path.deleteIfExists() = forceDelete(toFile())
 }