fix: format release note correctly for multiple same category commits (#1965)

Created release pull request in
#1966

Fixes #1957

Author: JoeWang1127

internal/librarian/release_notes.go

@@ -72,16 +72,12 @@ Language Image: {{.ImageVersion}}
 <details><summary>{{.LibraryID}}: {{.NewVersion}}</summary>
 
 ## [{{.NewVersion}}]({{"https://github.com/"}}{{.RepoOwner}}/{{.RepoName}}/compare/{{.PreviousTag}}...{{.NewTag}}) ({{.Date}})
-{{- range .CommitSections -}}
-{{- if .Commits -}}
-{{- if .Heading }}
-
+{{ range .CommitSections }}
 ### {{.Heading}}
-{{ end }}
-{{- range .Commits -}}
+{{ range .Commits }}
 * {{.Description}} ([{{shortSHA .SHA}}]({{"https://github.com/"}}{{$noteSection.RepoOwner}}/{{$noteSection.RepoName}}/commit/{{.SHA}}))
-{{- end }}
-{{- end }}
+{{ end }}
+
 {{- end }}
 </details>
 

internal/librarian/release_notes_test.go

@@ -529,10 +529,57 @@ Language Image: go:1.21
 ## [1.1.0](https://github.com/owner/repo/compare/my-library-1.0.0...my-library-1.1.0) (%s)
 
 ### Features
+
 * new feature ([1234567](https://github.com/owner/repo/commit/1234567890abcdef000000000000000000000000))
 
 ### Bug Fixes
+
 * a bug fix ([fedcba0](https://github.com/owner/repo/commit/fedcba0987654321000000000000000000000000))
+
+</details>`,
+				librarianVersion, today),
+		},
+		{
+			name: "single library with multiple features",
+			state: &config.LibrarianState{
+				Image: "go:1.21",
+				Libraries: []*config.LibraryState{
+					{
+						ID: "my-library",
+						// this is the NewVersion in the release note.
+						Version:         "1.1.0",
+						PreviousVersion: "1.0.0",
+						Changes: []*conventionalcommits.ConventionalCommit{
+							{
+								Type:        "feat",
+								Description: "new feature",
+								SHA:         hash1.String(),
+							},
+							{
+								Type:        "feat",
+								Description: "another new feature",
+								SHA:         hash2.String(),
+							},
+						},
+						ReleaseTriggered: true,
+					},
+				},
+			},
+			repo: &MockRepository{
+				RemotesValue: []*git.Remote{git.NewRemote(nil, &gitconfig.RemoteConfig{Name: "origin", URLs: []string{"https://github.com/owner/repo.git"}})},
+			},
+			wantReleaseNote: fmt.Sprintf(`Librarian Version: %s
+Language Image: go:1.21
+<details><summary>my-library: 1.1.0</summary>
+
+## [1.1.0](https://github.com/owner/repo/compare/my-library-1.0.0...my-library-1.1.0) (%s)
+
+### Features
+
+* new feature ([1234567](https://github.com/owner/repo/commit/1234567890abcdef000000000000000000000000))
+
+* another new feature ([fedcba0](https://github.com/owner/repo/commit/fedcba0987654321000000000000000000000000))
+
 </details>`,
 				librarianVersion, today),
 		},
@@ -581,7 +628,9 @@ Language Image: go:1.21
 ## [1.1.0](https://github.com/owner/repo/compare/lib-a-1.0.0...lib-a-1.1.0) (%s)
 
 ### Features
+
 * feature for a ([1234567](https://github.com/owner/repo/commit/1234567890abcdef000000000000000000000000))
+
 </details>
 
 
@@ -590,7 +639,9 @@ Language Image: go:1.21
 ## [2.0.1](https://github.com/owner/repo/compare/lib-b-2.0.0...lib-b-2.0.1) (%s)
 
 ### Bug Fixes
+
 * fix for b ([fedcba0](https://github.com/owner/repo/commit/fedcba0987654321000000000000000000000000))
+
 </details>`,
 				librarianVersion, today, today),
 		},
@@ -630,7 +681,9 @@ Language Image: go:1.21
 ## [1.1.0](https://github.com/owner/repo/compare/my-library-1.0.0...my-library-1.1.0) (%s)
 
 ### Features
+
 * new feature ([1234567](https://github.com/owner/repo/commit/1234567890abcdef000000000000000000000000))
+
 </details>`,
 				librarianVersion, today),
 		},