address more header names that are not canonicalized before use

[bmc-msft]

Because Header Names are canonicalized to lowercase, use of these headers broke when the headername implementation changed.

[bmc-msft]

It would be great if we could find a way to ensure header names are always canonicalized moving forwards. These were not caught during the shift from http::Request to azure_core::Request as part of #833.

For reference, our existing methods for creating HeaderName, which only check when we're creating them from String or Cow, but not when making static versions:

azure-sdk-for-rust/sdk/core/src/headers/mod.rs

Lines 174 to 206 in a2fc340

	impl HeaderName {
	pub const fn from_static(s: &'static str) -> Self {
	Self(std::borrow::Cow::Borrowed(s))
	}
	fn from_cow<C>(c: C) -> Self
	where
	C: Into<std::borrow::Cow<'static, str>>,
	{
	let c = c.into();
	assert!(
	c.chars().all(|c| c.is_lowercase() || !c.is_alphabetic()),
	"header names must be lowercase: {c}"
	);
	Self(c)
	}
	pub fn as_str(&self) -> &str {
	self.0.as_ref()
	}
	}
	impl From<&'static str> for HeaderName {
	fn from(s: &'static str) -> Self {
	Self::from_cow(s)
	}
	}
	impl From<String> for HeaderName {
	fn from(s: String) -> Self {
	Self::from_cow(s.to_lowercase())
	}
	}