Fix remaining issues for v1.4.4 map tiles display, etc.

[anthonyfok]

• Rollback from leaflet@1.9.4 to leaflet@1.7.1
  My previous bump to leaflet@1.9.4 broke _pages/en/dsra_scenario_map.md
  where clicking on a map tile no longer shows popup or feature table.

• Fix remaining issues with map tiles display on interactive maps

  • Point to https://riskprofiler-ca.github.io/ as the baseUrl
    for newly uploaded v1.4.4 tiles
  • Fix setTileLayerStyles() for some of the scenarios so the feature
    tiles are filled with the correct colour shades
  • Update setShakeLayerStyles() for the 3 renamed scenarios

• Use scenario title as heading for interactive maps
  for French support and for consistency with the titles used elsewhere
  on GitHub Pages and on www.riskprofiler.ca

• Change splash page title from Canada.ca to Earthquake Scenarios

• Change "epicenter" to "epicentre" Canadian spelling
  and remove trailing whitespace too

• Gemfile: Resolve "uninitialized constant TZInfo:Timezone (NameError)"
  that may be seen on Windows.

  Thanks to @Andre601 for sharing his solution on
  Exception on jekyll serve (Uninitialized constant) tzinfo/tzinfo#144 (comment)

A preview version is available at https://anthonyfok.github.io/earthquake-scenarios/

Many thanks!

[wkhchow]

Looks good to me. checked out the GH page. All tiles loaded fine although the OSM background didn't load for me, butt it was also the same thing on the opendrr.github.io page so as well.

[anthonyfok]

@wkhchow Thanks for your review and approval!

About the OSM base map, iIt seems that osm.gs.mil is down somehow? Their demo at https://osm.gs.mil/map/slippymap.html is currently not showing anything either. Accessing their tiles via e.g. https://osm.gs.mil/tiles/default_pc/7/38/30.png currently gives 504 Gateway Time-out... Hmm... Hope they resolve the issue soon!

Update: GEOINT OSM base map service was restored a day later on Friday, 2024-02-23.