Attachment progress info is lacking contrast

When uploading an attachment, a progress bar is displayed. The elements in this progress bar do not respect contrast minimum since they are dark grey on a light grey. The solution is either to remove the box light grey background around the attachment status, or change the text color to be darker.

This was first reported on CI by automated tests using Axe core:

WCAG warnings in the test class [org.xwiki.attachment.test.ui.docker.AllIT]:
__________

Validation in the test method [checkComment]
Check for [org.xwiki.flamingo.skin.test.po.AttachmentsViewPage] at http://xwikiweb:8080/xwiki/bin/view/NestedAttachmentCommentIT/checkComment/#Attachments.
Found [2] items

1: Elements must meet minimum color contrast ratio thresholds
Description: Ensures the contrast between foreground and background colors meets WCAG 2 AA minimum contrast ratio thresholds
Help URL: https://dequeuniversity.com/rules/axe/4.9/color-contrast?application=axeAPI
Help: Elements must meet minimum color contrast ratio thresholds
Impact: serious
Tags: cat.color, wcag2aa, wcag143, TTv5, TT13.c, EN-301-549, EN-9.1.4.3, ACT

HTML element: 
    <span class="progress-percentage">100%</span>
Selector: [.upload-status.upload-done:nth-child(1) > .progress-info > .progress-percentage]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-transfered">(13.0 b)</span>
Selector: [.upload-status.upload-done:nth-child(1) > .progress-info > .progress-transfered]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-speed">13.0 b/s</span>
Selector: [.upload-status.upload-done:nth-child(1) > .progress-info > .progress-time > .progress-speed]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-remaining"> | 00:00:00</span>
Selector: [.upload-status.upload-done:nth-child(1) > .progress-info > .progress-time > .progress-remaining]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-percentage">100%</span>
Selector: [.upload-status.upload-done:nth-child(2) > .progress-info > .progress-percentage]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-transfered">(13.0 b)</span>
Selector: [.upload-status.upload-done:nth-child(2) > .progress-info > .progress-transfered]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-speed">13.0 b/s</span>
Selector: [.upload-status.upload-done:nth-child(2) > .progress-info > .progress-time > .progress-speed]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1

HTML element: 
    <span class="progress-remaining"> | 00:00:00</span>
Selector: [.upload-status.upload-done:nth-child(2) > .progress-info > .progress-time > .progress-remaining]
Fix any of the following:
  Element has insufficient color contrast of 3.05 (foreground color: #888888, background color: #eeeeee, font size: 9.6pt (12.74px), font weight: normal). Expected contrast ratio of 4.5:1