I18N: Annotate indentation of the transaction summary

Translators are recommend to align the messages to prevent from
a broken table:

    Podsumowanie transakcji:
     Instalowanie:         6 pakietów
     Aktualizowanie:         33 pakietów
     Zastępowanie:         48 pakietów
     Usuwanie:         199 pakietów

Relates: https://bugzilla.redhat.com/show_bug.cgi?id=2336561

libdnf5-cli/output/transaction_table.cpp

@@ -128,48 +128,55 @@ class TransactionSummary {
         if (installs != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Installing:      {:4} package\n", " Installing:      {:4} packages\n", installs), installs)
                     .c_str(),
                 fd);
         }
         if (reinstalls != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Reinstalling:    {:4} package\n", " Reinstalling:    {:4} packages\n", reinstalls), reinstalls)
                     .c_str(),
                 fd);
         }
         if (upgrades != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Upgrading:       {:4} package\n", " Upgrading:       {:4} packages\n", upgrades), upgrades)
                     .c_str(),
                 fd);
         }
         if (replaced != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Replacing:       {:4} package\n", " Replacing:       {:4} packages\n", replaced), replaced)
                     .c_str(),
                 fd);
         }
         if (removes != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Removing:        {:4} package\n", " Removing:        {:4} packages\n", removes), removes)
                     .c_str(),
                 fd);
         }
         if (downgrades != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Downgrading:     {:4} package\n", " Downgrading:     {:4} packages\n", downgrades), downgrades)
                     .c_str(),
                 fd);
         }
         if (reason_changes != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Changing reason: {:4} package\n", " Changing reason: {:4} packages\n", reason_changes),
                     reason_changes)
                     .c_str(),
@@ -178,6 +185,7 @@ class TransactionSummary {
         if (skips != 0) {
             std::fputs(
                 libdnf5::utils::sformat(
+                    // Keep the replaceble number aligned across all messages.
                     P_(" Skipping:        {:4} package\n", " Skipping:        {:4} packages\n", skips), skips)
                     .c_str(),
                 fd);