Bump github.com/mattermost/mattermost-server/v6 from 6.1.0 to 6.3.0 (#1686)

Bumps [github.com/mattermost/mattermost-server/v6](https://github.com/mattermost/mattermost-server) from 6.1.0 to 6.3.0.
- [Release notes](https://github.com/mattermost/mattermost-server/releases)
- [Changelog](https://github.com/mattermost/mattermost-server/blob/master/CHANGELOG.md)
- [Commits](https://github.com/mattermost/mattermost-server/compare/v6.1.0...v6.3.0)

---
updated-dependencies:
- dependency-name: github.com/mattermost/mattermost-server/v6
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

vendor/gopkg.in/ini.v1/README.md

@@ -24,7 +24,7 @@ Package ini provides INI file read and write functionality in Go.
 
 ## Installation
 
-The minimum requirement of Go is **1.6**.
+The minimum requirement of Go is **1.12**.
 
 ```sh
 $ go get gopkg.in/ini.v1

vendor/gopkg.in/ini.v1/file.go

@@ -168,8 +168,9 @@ func (f *File) SectionsByName(name string) ([]*Section, error) {
 func (f *File) Section(name string) *Section {
 	sec, err := f.GetSection(name)
 	if err != nil {
-		// Note: It's OK here because the only possible error is empty section name,
-		// but if it's empty, this piece of code won't be executed.
+		if name == "" {
+			name = DefaultSection
+		}
 		sec, _ = f.NewSection(name)
 		return sec
 	}