Improvements of releases list and tags list (#25859)

Follow #23465 and #25624

This PR introduces the following improvements:
- We do not need to call `GetTags` to get tags because tags have been
loaded by `RepoAssignment`

ef90fdbd1d/modules/context/repo.go (L663-L668)
- Similarly, the number of tags and releases also have been loaded by
`RepoAssignment`, so the related code has been removed from the
handlers. The query condition of `GetReleaseCountByRepoID` in
`RepoAssignment` has been changed to include draft releases.

ef90fdbd1d/modules/context/repo.go (L538-L551)
- `releasesOrTags` function has been removed. The code for rendering
releases list and tags list moved to `Releases` and `TagList`
respectively.

routers/web/repo/release_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	repo_model "code.gitea.io/gitea/models/repo"
+	"code.gitea.io/gitea/models/unit"
 	"code.gitea.io/gitea/models/unittest"
 	"code.gitea.io/gitea/modules/contexttest"
 	"code.gitea.io/gitea/modules/web"
@@ -65,7 +66,7 @@ func TestNewReleasePost(t *testing.T) {
 	}
 }
 
-func TestNewReleasesList(t *testing.T) {
+func TestCalReleaseNumCommitsBehind(t *testing.T) {
 	unittest.PrepareTestEnv(t)
 	ctx, _ := contexttest.MockContext(t, "user2/repo-release/releases")
 	contexttest.LoadUser(t, ctx, 2)
@@ -73,8 +74,17 @@ func TestNewReleasesList(t *testing.T) {
 	contexttest.LoadGitRepo(t, ctx)
 	t.Cleanup(func() { ctx.Repo.GitRepo.Close() })
 
-	Releases(ctx)
-	releases := ctx.Data["Releases"].([]*repo_model.Release)
+	releases, err := repo_model.GetReleasesByRepoID(ctx, ctx.Repo.Repository.ID, repo_model.FindReleasesOptions{
+		IncludeDrafts: ctx.Repo.CanWrite(unit.TypeReleases),
+	})
+	assert.NoError(t, err)
+
+	countCache := make(map[string]int64)
+	for _, release := range releases {
+		err := calReleaseNumCommitsBehind(ctx.Repo, release, countCache)
+		assert.NoError(t, err)
+	}
+
 	type computedFields struct {
 		NumCommitsBehind int64
 		TargetBehind     string