Add unmaintained advisories (#2079)

* Add unmaintained advisories

* fix review findings & add typesize as alternative

crates/get-size-derive/RUSTSEC-0000-0000.md

@@ -0,0 +1,21 @@
+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "get-size-derive"
+date = "2024-09-15"
+informational = "unmaintained"
+url = "https://github.com/DKerp/get-size/issues/22"
+
+[versions]
+patched = []
+```
+
+# get-size-derive is unmaintained
+
+get-size-derive's maintainer seems to be unreachable, with no commits and releases pushed for 1 year and no activity on the GitHub repo.
+
+get-size-derive also depends on `attribute-derive ^0.6` a version of the crate which uses the yanked crate `proc-macro-error`.
+
+## Possible Alternative(s)
+
+- [get-size-derive2](https://crates.io/crates/get-size-derive2)

crates/get-size/RUSTSEC-0000-0000.md

@@ -0,0 +1,22 @@
+```toml
+[advisory]
+id = "RUSTSEC-0000-0000"
+package = "get-size"
+date = "2024-09-15"
+informational = "unmaintained"
+url = "https://github.com/DKerp/get-size/issues/22"
+
+[versions]
+patched = []
+```
+
+# get-size is unmaintained
+
+get-size's maintainer seems to be unreachable, with no commits and releases pushed for 1 year and no activity on the GitHub repo.
+
+get-size also depends on `get-size-derive 0.1.3`, which uses `attribute-derive ^0.6` a version of the crate which uses the yanked crate `proc-macro-error`.
+
+## Possible Alternative(s)
+
+- [get-size2](https://crates.io/crates/get-size2)
+- [typesize](https://crates.io/crates/typesize)