*sum: update pages to make them consistent (#10136)

* *sum: update pages to make them consistent

* md5sum: fix typo, shasum: change 'the' to 'a' for consistency

pages/common/b2sum.md

@@ -3,15 +3,15 @@
 > Calculate BLAKE2 cryptographic checksums.
 > More information: <https://www.gnu.org/software/coreutils/b2sum>.
 
-- Calculate the BLAKE2 checksum for a file:
+- Calculate the BLAKE2 checksum for one or more files:
 
-`b2sum {{path/to/file}}`
+`b2sum {{path/to/file1 path/to/file2 ...}}`
 
-- Calculate BLAKE2 checksums for multiple files:
+- Calculate and save the list of BLAKE2 checksums to a file:
 
-`b2sum {{path/to/file1}} {{path/to/file2}}`
+`b2sum {{path/to/file1 path/to/file2 ...}} > {{path/to/file.b2}}`
 
-- Calculate the BLAKE2 checksum from `stdin`:
+- Calculate a BLAKE2 checksum from `stdin`:
 
 `{{some_command}} | b2sum`
 
@@ -23,6 +23,6 @@
 
 `b2sum --check --quiet {{path/to/file.b2}}`
 
-- Only show a message for files for which verification fails, ignoring missing files:
+- Only show a message when verification fails, ignoring missing files:
 
 `b2sum --ignore-missing --check --quiet {{path/to/file.b2}}`