Add note under charts about the incomplete range

[brianlove]

Add a note underneath the trends charts specifying at what point the data become incomplete.

Closes #336

[github-actions[bot]]

No need for rebasing :+1: behind_count is 0 ahead_count is 1

[github-actions[bot]]

☂️ Python Coverage

current status: ✅

Overall Coverage

Lines	Covered	Coverage	Threshold	Status
572	370	65%	0%	🟢

New Files

No new covered files...

Modified Files

No covered modified files...

updated for commit: 62bf815 by action🐍

[github-actions[bot]]

JavaScript Coverage

Summary

Lines	Statements	Branches	Functions
	67.91% (398/586)	57.18% (191/334)	68.04% (132/194)

Modified Files • (67%)

File	% Stmts	% Branch	% Funcs	% Lines	Uncovered Line #s
All files	67.91	57.18	68.04	67.57
components	64.22	58.3	62.59	63.76
TrendsChart.jsx	0	0	0	0	11–73