fix (Alerts UI): Handle spaces in Explore names

[ericpgreen2]

Closes ENG-784

Note: I've checked Scheduled Reports, and we do not have this same issue.

Checklist:

• Covered by tests
• Ran it and it works as intended
• Reviewed the diff before requesting a review
• Checked for unhandled edge cases
• Linked the issues it closes
• Checked if the docs need to be updated. If so, create a separate Linear DOCS issue
• Intend to cherry-pick into the release branch
• I'm proud of this work!

[AdityaHegde]

Curious why this is not an issues for reports. The link in ReportMetadata and the gotoExplorePage have similar code as in alerts.

[ericpgreen2]

Curious why this is not an issues for reports

• For Alerts, we provide a web_open_path annotation. Confusingly, we don't directly navigate to the web_open_path, but instead we parse it for the exploreName, which we use to compose a different URL (one with URL state). The bug was that we weren't correctly parsing the web_open_path for the exploreName when the exploreName included spaces.
• For Reports, we no longer provide a web_open_path annotation. Instead, we explicitly provide the explore resource name. So, there's no bug with Reports, as they don’t rely on web_open_path at all.

It'd be a good clean-up if we used the Report approach for Alerts too.