Enforce required, optional, and rest positional arguments start with an uppercase and end with a period. (#11285)

# Description

This updates all the positional arguments (except with
`--features=dataframe` or `--features=extra`) to start with an uppercase
letter and end with a period.

Part of #5066, specifically [this
comment](/nushell/nushell/issues/5066#issuecomment-1421528910)

Some arguments had example data removed from them because it also
appears in the examples.

There are other inconsistencies in positional arguments I noticed while
making the tests pass which I will bring up in #5066.

# User-Facing Changes

Positional arguments are now consistent

# Tests + Formatting

- 🟢 `toolkit fmt`
- 🟢 `toolkit clippy`
- 🟢 `toolkit test`
- 🟢 `toolkit test stdlib`

# After Submitting

Automatic documentation updates

crates/nu-command/src/database/commands/into_sqlite.rs

@@ -25,7 +25,7 @@ impl Command for IntoSqliteDb {
             .required(
                 "file_name",
                 SyntaxShape::String,
-                "Specify the filename to save the database to",
+                "Specify the filename to save the database to.",
             )
             .named(
                 "table_name",

crates/nu-command/src/database/commands/query_db.rs

@@ -22,7 +22,7 @@ impl Command for QueryDb {
             .required(
                 "SQL",
                 SyntaxShape::String,
-                "SQL to execute against the database",
+                "SQL to execute against the database.",
             )
             .category(Category::Database)
     }