add info section for data.gov/metrics concerning foreign language values in reports

## User Story

In order to inform users about the validity of reporting data in metrics, data.gov wants to add an info section to /metrics indicating foreign language values in reports can be acceptable

## Acceptance Criteria

[ACs should be clearly demoable/verifiable whenever possible. Try specifying them using [BDD](https://en.wikipedia.org/wiki/Behavior-driven_development#Behavioral_specifications).]

- [ ] GIVEN there have been [concerns](https://github.com/GSA/data.gov/issues/6314) about foreign languages in metric reports \
WHEN the info section displays on the page \
THEN users are aware that foreign language values in reports are valid \

## Background

[Any helpful contextual notes or links to artifacts/evidence, if needed]

## Security Considerations ([required](https://nvd.nist.gov/800-53/Rev4/control/CM-4))

[comment]: # "Our SSP says 'The Data.gov team ensures security implications are considered as part of the agile requirements refinement process by including a section in the issue template used as a basis for new work.' so please don't remove this section without care."
[Any security concerns that might be implicated in the change. "None" is OK, just be explicit here!]

## Sketch

[Notes or a checklist reflecting our understanding of the selected approach]

Start at the /metrics page and read the concerns in issue #6314 for the wording and context. Add a visible info section explaining that foreign-language values in reports can be valid, then verify the message appears on /metrics and clearly communicates that point.

Written by the indexing model from the issue text.