Update dependencies (#843)

log:

```
    Updating crates.io index
    Updating anyhow v1.0.40 -> v1.0.41
    Updating bumpalo v3.6.1 -> v3.7.0
    Updating cc v1.0.67 -> v1.0.68
    Updating crossbeam-epoch v0.9.4 -> v0.9.5
    Updating crossbeam-utils v0.8.4 -> v0.8.5
    Updating git2 v0.13.17 -> v0.13.20
    Updating httpdate v1.0.0 -> v1.0.1
    Updating hyper v0.14.7 -> v0.14.9
    Updating ipnet v2.3.0 -> v2.3.1
    Updating libc v0.2.94 -> v0.2.97
    Updating libgit2-sys v0.12.20+1.1.0 -> v0.12.21+1.1.0
    Updating memoffset v0.6.3 -> v0.6.4
    Updating mio v0.7.11 -> v0.7.13
    Updating once_cell v1.7.2 -> v1.8.0
    Updating openssl v0.10.34 -> v0.10.35
    Updating openssl-sys v0.9.63 -> v0.9.64
    Removing pin-project v1.0.7
    Removing pin-project-internal v1.0.7
    Updating rand v0.8.3 -> v0.8.4
    Updating rand_chacha v0.3.0 -> v0.3.1
    Updating rand_core v0.6.2 -> v0.6.3
    Updating rand_hc v0.3.0 -> v0.3.1
    Updating redox_syscall v0.2.8 -> v0.2.9
    Updating security-framework v2.2.0 -> v2.3.1
    Updating security-framework-sys v2.2.0 -> v2.3.0
    Updating syn v1.0.72 -> v1.0.73
    Updating tokio v1.6.0 -> v1.7.1
    Updating unicode-normalization v0.1.17 -> v0.1.19
    Updating vcpkg v0.2.13 -> v0.2.15
```