chore(ci): Speed up edge build

[RemiBardon]

I tried different cargo profile configurations, and I came up with better settings to speed up all builds. I also created a staging profile which we will now use when building edge. It should be about 2 times quicker now.

Fixes #104.

Here are my benchmarks (not a source of truth, more like notes for myself):

[profile.release]
opt-level = "s"
lto = true
debug = false
debug-assertions = false
panic = "abort"

  594.97 real         4.13 user         5.82 sys

27.7MB

---

[profile.release]
opt-level = "s"
lto = "thin"
debug = false
debug-assertions = false
panic = "abort"

  605.31 real         4.33 user         5.13 sys

34.1MB

---

[profile.release]
opt-level = 2
lto = "thin"
debug = false
debug-assertions = false
panic = "abort"

  675.15 real         4.72 user         6.41 sys

37.9MB

---

[profile.release]
opt-level = 1
lto = "thin"
debug = false
debug-assertions = false
panic = "abort"

  610.94 real         4.35 user         5.50 sys

37MB

---

[profile.release]
opt-level = 0
lto = "thin"
debug = false
debug-assertions = false
panic = "abort"

  356.43 real         3.07 user         4.41 sys

68.5MB

---

[profile.dev]
opt-level = 0
debug = true
debug-assertions = true

[profile.staging]
inherits = "dev"
opt-level = 1
debug-assertions = false

---

  747.32 real         5.05 user         5.78 sys

390MB

[profile.dev]
opt-level = 0
debug = true
debug-assertions = true

[profile.staging]
inherits = "dev"
lto = "thin"
debug-assertions = false

  506.68 real         3.69 user         4.67 sys

301MB

---

[profile.dev]
opt-level = 0
debug = true
debug-assertions = true

[profile.staging]
inherits = "dev"
lto = "thin"
debug = false
debug-assertions = false
panic = "abort"

  405.74 real         3.28 user         4.44 sys

68.8MB

---

[profile.dev]
opt-level = 0
debug = true
debug-assertions = true

[profile.staging]
inherits = "dev"
lto = "thin"
debug = false
debug-assertions = false
panic = "abort"
incremental = true

  420.29 real         3.61 user         5.18 sys

68.8MB

---

[profile.release]
opt-level = "s"
lto = "thin"
debug = false
debug-assertions = false
strip = "symbols"
panic = "abort"

  591.12 real         4.19 user         5.08 sys

28.6MB

---

[profile.dev]
opt-level = 0
debug = true
debug-assertions = true

  318.66 real         2.88 user         3.98 sys

357MB

---

[profile.dev]
opt-level = 0
debug = false
debug-assertions = true

  278.41 real         2.84 user         4.12 sys

76.4MB