Cannot change a group avatar
### Summary
Admin user is not able to change the group avatar by clicking the `Choose file...` button, however it's possible by clicking the `Group avatar` text to the left of the `Choose file...` button.
### Steps to reproduce
I am using Chrome 74 on Windows.
1. Go to Admin area
2. Select a Group without avatar to edit
3. Click Edit button
4. Click Choose file... for Group avatar
5. Nothing happens, file dialog is not opened.
6. A file dialog opens if you click the `Group avatar` label to the left of `Choose file...`
### Example Project
No such.
### What is the current *bug* behavior?
The file dialog is not opened when clicking `Choose file...` so the admin cannot change the avatar this way. However, it seems if you click the `Group avatar` text label to left of the `Choose file...` button, a file dialog will appear.
### What is the expected *correct* behavior?
The file dialog should be opened when clicking the `Choose file...` button, and from there an admin should be able to select and upload an avatar for the group.
### Relevant logs and/or screenshots

### Output of checks
(If you are reporting a bug on GitLab.com, write: This bug happens on GitLab.com)
#### Results of GitLab environment info
<details>
<summary>Expand for output related to GitLab environment info</summary>
<pre>
System information
System:
Proxy: no
Current User: git
Using RVM: no
Ruby Version: 2.5.3p105
Gem Version: 2.7.6
Bundler Version:1.17.3
Rake Version: 12.3.2
Redis Version: 3.2.12
Git Version: 2.18.1
Sidekiq Version:5.2.5
Go Version: unknown
GitLab information
Version: 11.10.2-ee
Revision: 1aafae9879c
Directory: /opt/gitlab/embedded/service/gitlab-rails
DB Adapter: PostgreSQL
DB Version: 9.6.11
URL: https://gitlab.*.*
HTTP Clone URL: https://gitlab.*.*/some-group/some-project.git
SSH Clone URL: git@gitlab.*.*:some-group/some-project.git
Elasticsearch: no
Geo: no
Using LDAP: yes
Using Omniauth: yes
Omniauth Providers:
GitLab Shell
Version: 9.0.0
Repository storage paths:
\- default: /var/opt/gitlab/git-data/repositories
GitLab Shell path: /opt/gitlab/embedded/service/gitlab-shell
Git: /opt/gitlab/embedded/bin/git
</pre>
</details>
#### Results of GitLab application Check
<details>
<summary>Expand for output related to the GitLab application check</summary>
<pre>
Checking GitLab subtasks ...
Checking GitLab Shell ...
GitLab Shell: ... GitLab Shell version >= 9.0.0 ? ... OK (9.0.0)
Running /opt/gitlab/embedded/service/gitlab-shell/bin/check
Check GitLab API access: OK
Redis available via internal API: OK
Access to /var/opt/gitlab/.ssh/authorized_keys: OK
gitlab-shell self-check successful
Checking GitLab Shell ... Finished
Checking Gitaly ...
Gitaly: ... default ... OK
Checking Gitaly ... Finished
Checking Sidekiq ...
Sidekiq: ... Running? ... yes
Number of Sidekiq processes ... 1
Checking Sidekiq ... Finished
Checking Incoming Email ...
Incoming Email: ... Reply by email is disabled in config/gitlab.yml
Checking Incoming Email ... Finished
Checking LDAP ...
censored
Checking LDAP ... Finished
Checking GitLab App ...
Git configured correctly? ... yes
Database config exists? ... yes
All migrations up? ... yes
Database contains orphaned GroupMembers? ... no
GitLab config exists? ... yes
GitLab config up to date? ... yes
Log directory writable? ... yes
Tmp directory writable? ... yes
Uploads directory exists? ... yes
Uploads directory has correct permissions? ... yes
Uploads directory tmp has correct permissions? ... yes
Init script exists? ... skipped (omnibus-gitlab has no init script)
Init script up-to-date? ... skipped (omnibus-gitlab has no init script)
Projects have namespace: ...
3/1 ... yes
Redis version >= 2.8.0? ... yes
Ruby version >= 2.5.3 ? ... yes (2.5.3)
Git version >= 2.18.0 ? ... yes (2.18.1)
Git user has default SSH configuration? ... yes
Active users: ... 4
Elasticsearch version 5.6 - 6.x? ... skipped (elasticsearch is disabled)
Checking GitLab App ... Finished
Checking GitLab subtasks ... Finished
</pre>
</details>
### Possible fixes / workarounds
It's possible to upload a group avatar if you click the `Group avatar` label to the left of the `Choose file...` button as pointed out in - https://gitlab.com/gitlab-org/gitlab/-/issues/28389#note_496744575
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