Fix whitespace warnings

spec/help_spec.lua

@@ -51,7 +51,7 @@ An epilog.]], parser:get_help())
          :args "2"
       parser:argument "maybe-fourth"
          :args "?"
-      parser:argument("others", "Optional. ")
+      parser:argument("others", "Optional.")
          :args "*"
 
       assert.equal([[
@@ -94,7 +94,7 @@ Options:
          :description [[
 Sets verbosity level.
 -v: Report all warnings.
--vv: Report all debugging information. ]]
+-vv: Report all debugging information.]]
 
       assert.equal([[
 Usage: foo [-v] [-h]
@@ -131,7 +131,7 @@ Options:
       parser:option "-p"
          :default "8080"
          :show_default(false)
-         :description "Port. "
+         :description "Port."
 
       assert.equal([[
 Usage: foo [-o <o>] [-p <p>] [-h]

spec/script.lua

@@ -2,28 +2,28 @@
 local Parser = require "argparse"
 
 local parser = Parser()
-   :description "A testing program. "
+   :description "A testing program."
    :require_command(false)
 
 parser:argument "input"
 
 parser:flag "-v" "--verbose"
-   :description "Sets verbosity level. "
+   :description "Sets verbosity level."
    :target "verbosity"
    :count "0-2"
 
 local install = parser:command "install"
-   :description "Install a rock. "
+   :description "Install a rock."
 
 install:argument "rock"
-   :description "Name of the rock. "
+   :description "Name of the rock."
 
 install:argument "version"
-   :description "Version of the rock. "
+   :description "Version of the rock."
    :args "?"
 
 install:option "-f" "--from"
-   :description "Fetch the rock from this server. "
+   :description "Fetch the rock from this server."
    :target "server"
 
 parser:get_usage()