docs: add version in past CHANGELOGs

kenjis · kenjis · commit 8de71cf91899 · 2023-01-17T09:59:38.000+09:00
diff --git a/changelogs/CHANGELOG_4.0.md b/changelogs/CHANGELOG_4.0.md
@@ -1,4 +1,4 @@
-# Changelog
+# Changelog 4.0
 
 ## [v4.0.5](https://github.com/codeigniter4/CodeIgniter4/tree/v4.0.5) (2021-01-31)
 
diff --git a/changelogs/CHANGELOG_4.1.md b/changelogs/CHANGELOG_4.1.md
@@ -1,4 +1,4 @@
-# Changelog
+# Changelog 4.1
 
 ## [v4.1.9](https://github.com/codeigniter4/CodeIgniter4/tree/v4.1.9) (2022-02-25)
 

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-# Changelog`
	`1`	`+# Changelog 4.0`
`2`	`2`
`3`	`3`	`## [v4.0.5](https://github.com/codeigniter4/CodeIgniter4/tree/v4.0.5) (2021-01-31)`
`4`	`4`
Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-# Changelog`
	`1`	`+# Changelog 4.1`
`2`	`2`
`3`	`3`	`## [v4.1.9](https://github.com/codeigniter4/CodeIgniter4/tree/v4.1.9) (2022-02-25)`
`4`	`4`