fix(cli): stat: explicitly specify resource SI prefix (#8206)

* fix(cli): move to explicitly specifying units

* make gen

cli/testdata/coder_stat_cpu_--help.golden

@@ -9,8 +9,5 @@ Show CPU usage, in cores.
   -o, --output string (default: text)
           Output format. Available formats: text, json.
 
-      --prefix string
-          Unit prefix.
-
 ---
 Run `coder --help` for a list of global options.

cli/testdata/coder_stat_disk_--help.golden

@@ -9,5 +9,8 @@ Show disk usage, in gigabytes.
       --path string (default: /)
           Path for which to check disk usage.
 
+      --prefix Ki|Mi|Gi|Ti (default: Gi)
+          SI Prefix for disk measurement.
+
 ---
 Run `coder --help` for a list of global options.

cli/testdata/coder_stat_mem_--help.golden

@@ -9,5 +9,8 @@ Show memory usage, in gigabytes.
   -o, --output string (default: text)
           Output format. Available formats: text, json.
 
+      --prefix Ki|Mi|Gi|Ti (default: Gi)
+          SI Prefix for memory measurement.
+
 ---
 Run `coder --help` for a list of global options.