fix: Bump launchdarkly-sdk-transport to 0.1.4

[keelerm84]

Summary

Follow-up to the rust-sdk-transport change (transport 0.1.4 is published).

launchdarkly-sdk-transport 0.1.4 requires hyper-http-proxy ^1.1.1, which removed its dependency on the unmaintained rustls-pemfile crate (RUSTSEC-2025-0134). This raises the transport floor from 0.1.0 to 0.1.4 in both launchdarkly-server-sdk and contract-tests so fresh dependency resolution can no longer select a transport version that drags rustls-pemfile into the tree. With this bump, rustls-pemfile no longer appears in the resolved dependency tree.

Fixes #176.

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Note

Low Risk
Dependency version floor only; no runtime or API changes in this repo, with expected benefit of clearing a known advisory from the tree.

Overview
Raises the minimum launchdarkly-sdk-transport version from 0.1.0 to 0.1.4 in launchdarkly-server-sdk and contract-tests so dependency resolution cannot pull in older transport releases that transitively depend on the unmaintained rustls-pemfile crate (RUSTSEC-2025-0134).

Transport 0.1.4 aligns with hyper-http-proxy ^1.1.1, which drops that dependency; this is a manifest-only change with no SDK source edits.

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[keelerm84]

Closing as unnecessary. The transport dependency is declared as version = "0.1.0" (= ^0.1.0), which already permits 0.1.4, so a fresh resolve / cargo update picks transport 0.1.4 -> hyper-http-proxy 1.1.1 and drops rustls-pemfile without this floor bump. Verified a from-scratch lockfile resolves to transport 0.1.4 and contains zero rustls-pemfile entries. The transport 0.1.4 release fully resolves RUSTSEC-2025-0134 for consumers.