7ab8b0c release cleanup: bump version after 0.7.0 (Jonas Nick)

Pull request description:

  Based on #1707.

ACKs for top commit:
  real-or-random:
    utACK 7ab8b0c

Tree-SHA512: 2eea54938ffa2a2c0503607566cb2900b76d5ff6d6285c65afe6fc09fa8b961f210ad915276618c5f43e3ade55252d6533c4c72a5e12c4db4c30fb20235a88df

Pulls in relevant changes from C2SP/wycheproof#150.

The CMake cache is global in scope. Therefore, setting the standard
cache variable `BUILD_SHARED_LIBS` can inadvertently affect the behavior
of a parent project.

This change:
1. Sets the `BUILD_SHARED_LIBS` cache variable only when libsecp256k1 is
   the top-level project.
2. Removes the `SECP256K1_DISABLE_SHARED` cache variable. This enables
   parent projects that include libsecp256k1 as a subproject to rely
   solely on standard CMake variables for configuring the library type.

5433648 Fix typos and spellings (Adrien Ufferte)
9ea54c6 tests: update Wycheproof files (fanquake)

Pull request description:

ACKs for top commit:
  real-or-random:
    ACK 5433648
  josibake:
    ACK 5433648

Tree-SHA512: abc39f898263da81b53da5223916f079878d31cca850384dd135ee555e7086ecfdbff1d329bf61438d188d76ad87dc610f119009ad91c0d2f8f3fdf99dc12e7a

…BUILD_SHARED_LIBS`

7b07b22 cmake: Avoid contaminating parent project's cache with BUILD_SHARED_LIBS (Hennadii Stepanov)

Pull request description:

  The CMake cache is global in scope. Therefore, setting the standard cache variable `BUILD_SHARED_LIBS` can inadvertently affect the behavior of a parent project.

  Consider configuring Bitcoin Core without explicit setting `BUILD_SHARED_LIBS`:
  ```
  $ cmake -B build -DBUILD_KERNEL_LIB=ON
  ```

  According to CMake’s documentation, this should configure `libbitcoinkernel` as `STATIC`.
  However, that's not the case:
  ```
  $ cmake --build build -t libbitcoinkernel
  [143/143] Linking CXX shared library lib/libbitcoinkernel.so
  ```

  This PR:
  1. Sets the `BUILD_SHARED_LIBS` cache variable only when `libsecp256k1` is the top-level project.
  2. Removes the `SECP256K1_DISABLE_SHARED` cache variable. This enables parent projects that include libsecp256k1 as a subproject to rely solely on standard CMake variables for configuring the library type.  During integration into a parent project, the static library can be forced as demonstrated [here](bitcoin-core/minisketch#75 (comment)).

ACKs for top commit:
  purpleKarrot:
    ACK 7b07b22
  theuni:
    utACK 7b07b22

Tree-SHA512: 399a02e86093656ce70d9a0292a1f30834bcc5b9cf0f77d6465adc5e8a4d8e779684adedc40942eb931fed857399e4176a23fdbdf45f277184b28159fbc932d2