Revert vim mode colors in One theme (#56772)

We originally added support for these keys to allow people to customize
the pill. As I noted at the time, we'd like the default to be more
visually minimal.

Release Notes:

- Reverted the colored vim mode indicator pill in the One Light and One
Dark themes (#56662)

assets/themes/one/one.json

@@ -104,14 +104,6 @@
         "version_control.deleted": "#e06c76ff",
         "version_control.conflict_marker.ours": "#a1c1811a",
         "version_control.conflict_marker.theirs": "#74ade81a",
-        "vim.normal.background": "#485e82",
-        "vim.insert.background": "#825b48",
-        "vim.visual.background": "#488251",
-        "vim.replace.background": "#827d48",
-        "vim.visual_line.background": "#488268",
-        "vim.visual_block.background": "#488276",
-        "vim.helix_normal.background": "#485e82",
-        "vim.helix_select.background": "#488251",
         "conflict": "#dec184ff",
         "conflict.background": "#dec1841a",
         "conflict.border": "#5d4c2fff",
@@ -524,14 +516,6 @@
         "version_control.word_added": "#2EA04859",
         "version_control.word_deleted": "#F85149CC",
         "version_control.deleted": "#e06c76ff",
-        "vim.normal.background": "#b0c8e8",
-        "vim.insert.background": "#e8c0a8",
-        "vim.visual.background": "#b0dcb8",
-        "vim.replace.background": "#e0dcb0",
-        "vim.visual_line.background": "#b0dccc",
-        "vim.visual_block.background": "#b0d4dc",
-        "vim.helix_normal.background": "#b0c8e8",
-        "vim.helix_select.background": "#b0dcb8",
         "conflict": "#a48819ff",
         "conflict.background": "#faf2e6ff",
         "conflict.border": "#f4e7d1ff",