test-infra: add curl validation on windows

[v1v]

What does this PR do?

Validate curl with test-infra

Why is it important?

Somehow Beats scripts don't find the curl installer and try to install it again.

[2021-03-31T07:34:21.427Z] C:\Users\jenkins\workspace\PR-24852-3-953a207b-0e8b-46d4-be83-0a2272f81bed\src\github.com\elastic\beats>where /q curl 
[2021-03-31T07:34:21.689Z] 
[2021-03-31T07:34:21.689Z] C:\Users\jenkins\workspace\PR-24852-3-953a207b-0e8b-46d4-be83-0a2272f81bed\src\github.com\elastic\beats>IF ERRORLEVEL 1 (choco install curl -y --no-progress --skipdownloadcache ) 
[2021-03-31T07:34:22.086Z] Chocolatey v0.10.15
[2021-03-31T07:34:22.086Z] Installing the following packages:
[2021-03-31T07:34:22.086Z] curl
[2021-03-31T07:34:22.086Z] By installing you accept licenses for the packages.
[2021-03-31T07:34:22.346Z] Error retrieving packages from source 'https://chocolatey.org/api/v2/':
[2021-03-31T07:34:22.346Z]  The remote server returned an error: (503) Server Unavailable.
[2021-03-31T07:34:22.606Z] curl not installed. The package was not found with the source(s) listed.
[2021-03-31T07:34:22.607Z]  Source(s): 'https://chocolatey.org/api/v2/'

Hopefully if it's there we can easily change the script from where /q curl to curl and if it fails then do the installation instead.

[apmmachine]

💚 Build Succeeded

the below badges are clickable and redirect to their specific view in the CI or DOCS

Expand to view the summary

Build stats

• Build Cause: Pull request #1069 updated

• Start Time: 2021-04-07T15:14:55.988+0000

• Duration: 34 min 34 sec

• Commit: a814c3d

Test stats 🧪

Test	Results
Failed	0
Passed	1126
Skipped	2
Total	1128

Trends 🧪

💚 Flaky test report

Tests succeeded.

Expand to view the summary

Test stats 🧪

Test	Results
Failed	0
Passed	1126
Skipped	2
Total	1128