cargo install pijul: get the right version without constantly updating the manual

Dependencies

• [2] XDGLFBST version 1.0.0-alpha.24
• [3] ONXLUQLI Add install instructions for arch
• [4] OSJ2HIDP Version 1.0.0-alpha.10
• [5] I26FNFRT Latest release
• [6] BRV6TU4B Turning the Installation page more beginner-friendly
• [7] BA5KMNO5 Updating installation instructions
• [8] SCSV2FNS Reboot

Change contents

• replacement in src/installing.md at line 51
  [3.308207]→[2.1:46](∅→∅)
  − cargo install pijul --version 1.0.0-alpha.24
  [3.308207]

  [3.233]
  + cargo install pijul --version 1.0.0-alpha